Tüm alıştırma soruları

5556 soru

Soru 2341Soru

In the standard (x,y)(x, y) coordinate plane, the circle defined by x2+y2=26x^2 + y^2 = 26 and the line defined by y=x4y = x - 4 intersect at two points. What is the distance between these two points of intersection?

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Cevap: 626\sqrt{2}

Cevap

626\sqrt{2}
Solving the system of equations by substituting y=x4y = x - 4 into x2+y2=26x^2 + y^2 = 26 yields 2x28x10=02x^2 - 8x - 10 = 0, which simplifies to x24x5=0x^2 - 4x - 5 = 0. Factoring gives (x5)(x+1)=0(x-5)(x+1) = 0, leading to the points (5,1)(5, 1) and (1,5)(-1, -5). The distance between these points is 62+62=62\sqrt{6^2 + 6^2} = 6\sqrt{2}.

Adım Adım Çözüm

1
Substitute the linear equation into the circle equation.
x2+(x4)2=26x^2 + (x - 4)^2 = 26
This reduces the system to a single equation in terms of xx.
2
Expand the squared binomial and simplify the quadratic equation.
2x28x10=02x^2 - 8x - 10 = 0, which simplifies to x24x5=0x^2 - 4x - 5 = 0.
Expanding (x4)2(x - 4)^2 yields x28x+16x^2 - 8x + 16. Setting the equation to zero allows us to solve for xx.
3
Factor the quadratic equation to find the xx-coordinates.
x=5x = 5 or x=1x = -1.
The factored form is (x5)(x+1)=0(x - 5)(x + 1) = 0.
4
Substitute the xx-values back into the linear equation to find the corresponding yy-coordinates.
The intersection points are (5,1)(5, 1) and (1,5)(-1, -5).
For x=5x = 5, y=54=1y = 5 - 4 = 1. For x=1x = -1, y=14=5y = -1 - 4 = -5.
5
Apply the distance formula to find the straight-line distance between the two points.
626\sqrt{2}
The distance is (5(1))2+(1(5))2=62+62=72=62\sqrt{(5 - (-1))^2 + (1 - (-5))^2} = \sqrt{6^2 + 6^2} = \sqrt{72} = 6\sqrt{2}.

Anahtar Kavram

Solving systems of linear and non-linear (circular) equations by substitution and finding the distance between intersection points.
Soru 2342Soru

In ABC\triangle ABC, the measure of B\angle B is 8080^\circ and the measure of C\angle C is 4040^\circ. A point DD lies on side BCBC such that ADAD bisects BAC\angle BAC, and a point EE lies on side ACAC such that AD=AEAD = AE. What is the measure, in degrees, of CDE\angle CDE?

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Cevap: 35

Cevap

35
The correct answer is 3535. By first finding that BAC=60\angle BAC = 60^\circ, we use the angle bisector ADAD to find CAD=30\angle CAD = 30^\circ. In ADC\triangle ADC, we find the interior angle ADC=110\angle ADC = 110^\circ. In the isosceles triangle ADE\triangle ADE with AD=AEAD=AE, the base angles are ADE=AED=75\angle ADE = \angle AED = 75^\circ. Finally, subtracting ADE\angle ADE from ADC\angle ADC gives CDE=35\angle CDE = 35^\circ.

Adım Adım Çözüm

1
Find the measure of the third angle of the main triangle, BAC\angle BAC.
BAC=60\angle BAC = 60^\circ
The sum of the interior angles of any triangle is 180180^\circ. Therefore, BAC=180BC=1808040=60\angle BAC = 180^\circ - \angle B - \angle C = 180^\circ - 80^\circ - 40^\circ = 60^\circ.
2
Determine the measure of the bisected angle CAD\angle CAD.
CAD=30\angle CAD = 30^\circ
Since ADAD bisects BAC\angle BAC, it divides the angle into two equal parts: BAD=CAD=602=30\angle BAD = \angle CAD = \frac{60^\circ}{2} = 30^\circ.
3
Calculate the interior angle ADC\angle ADC in ADC\triangle ADC.
ADC=110\angle ADC = 110^\circ
In ADC\triangle ADC, the sum of angles is 180180^\circ. Therefore, ADC=180CADC=1803040=110\angle ADC = 180^\circ - \angle CAD - \angle C = 180^\circ - 30^\circ - 40^\circ = 110^\circ.
4
Find the base angles of the isosceles triangle ADEADE.
ADE=75\angle ADE = 75^\circ
Since AD=AEAD = AE, ADE\triangle ADE is an isosceles triangle with vertex angle DAE=30\angle DAE = 30^\circ. The two base angles, ADE\angle ADE and AED\angle AED, are equal. Thus, ADE=180302=75\angle ADE = \frac{180^\circ - 30^\circ}{2} = 75^\circ.
5
Determine the final angle CDE\angle CDE by subtraction.
CDE=35\angle CDE = 35^\circ
Since point EE lies on side ACAC, ray DEDE lies between rays DADA and DCDC. Therefore, ADC=ADE+CDE\angle ADC = \angle ADE + \angle CDE. Rearranging gives CDE=ADCADE=11075=35\angle CDE = \angle ADC - \angle ADE = 110^\circ - 75^\circ = 35^\circ.

Anahtar Kavram

Applying triangle angle sum theorem, angle bisector properties, and isosceles triangle base angle properties to perform multi-step angle tracing.

Alternatif Yöntem

Use the exterior angle theorem on ADC\triangle ADC at vertex DD: ADB=CAD+C=30+40=70\angle ADB = \angle CAD + \angle C = 30^\circ + 40^\circ = 70^\circ. Then, since EE is on ACAC, AA, EE, and CC are collinear. In ADE\triangle ADE, the exterior angle at EE is DEC=DAE+ADE=30+75=105\angle DEC = \angle DAE + \angle ADE = 30^\circ + 75^\circ = 105^\circ. In DEC\triangle DEC, the sum of angles is 180180^\circ, so CDE=18010540=35\angle CDE = 180^\circ - 105^\circ - 40^\circ = 35^\circ.
Tahmini Süre:2m 30s
Soru 2343Soru

In the standard (x,y)(x,y) coordinate plane, a triangle has vertices at A(1,2)A(1, 2), B(9,2)B(9, 2), and C(5,8)C(5, 8). A horizontal line defined by the equation y=ky = k divides the area of the triangle into two regions of equal area. What is the value of kk?

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Cevap: 8328 - 3\sqrt{2}

Cevap

8328 - 3\sqrt{2}
The correct answer is 8328 - 3\sqrt{2}. Because the horizontal line y=ky=k is parallel to the base of the triangle, it creates a smaller top triangle similar to the original one. The area of the original triangle is 2424 and the area of the smaller triangle is 1212, yielding an area ratio of 12\frac{1}{2}. The height of the original triangle is 66, and the height of the smaller triangle is 8k8-k. Since the ratio of the areas of similar triangles is the square of the ratio of their heights, we write 12=(8k6)2\frac{1}{2} = \left(\frac{8-k}{6}\right)^2. Solving this equation yields k=832k = 8 - 3\sqrt{2}.

Adım Adım Çözüm

1
Calculate the area of the entire triangle ABCABC.
The base AB\overline{AB} is horizontal along y=2y = 2 with a length of 91=89 - 1 = 8. The height is the vertical distance from y=2y = 2 to the vertex C(5,8)C(5, 8), which is 82=68 - 2 = 6. The area of ABC\triangle ABC is 12×8×6=24\frac{1}{2} \times 8 \times 6 = 24.
Finding the total area is necessary to determine the target area of the divided regions.
2
Find the area of the smaller triangle formed above the line y=ky = k.
The line y=ky = k divides the triangle into a smaller top triangle and a bottom trapezoid. Since both regions have equal areas, the area of the smaller top triangle is 242=12\frac{24}{2} = 12.
The line divides the original area of 2424 into two equal parts of 1212 each.
3
Set up the area ratio equation using the properties of similar triangles.
The smaller top triangle is similar to ABC\triangle ABC because its base is parallel to AB\overline{AB}. The ratio of their areas is the square of the ratio of their heights: 1224=(8k6)2    12=(8k6)2\frac{12}{24} = \left(\frac{8 - k}{6}\right)^2 \implies \frac{1}{2} = \left(\frac{8 - k}{6}\right)^2.
For similar figures, the area ratio is equal to the square of the scale factor.
4
Solve the ratio equation for kk.
Taking the square root of both sides gives 12=8k6\frac{1}{\sqrt{2}} = \frac{8 - k}{6}, which simplifies to 22=8k6\frac{\sqrt{2}}{2} = \frac{8 - k}{6}. Multiplying both sides by 66 gives 32=8k3\sqrt{2} = 8 - k, which yields k=832k = 8 - 3\sqrt{2}.
This isolates kk to find the exact vertical coordinate of the dividing line.

Anahtar Kavram

Using properties of similar figures to determine areas and coordinates on the coordinate plane.
Soru 2344Soru

A drone starts at position PP on a grid. The drone's path is programmed with a sequence of two movements: first, it is translated 66 units to the right and 55 units up, and then its position is reflected across the yy-axis. If the drone's final position is (4,8)(-4, 8), what were the coordinates of its starting position PP?

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Cevap: (2,3)(-2, 3)

Cevap

The correct answer is (2,3)(-2, 3) because working backward from the final position (4,8)(-4, 8) by undoing the reflection across the yy-axis gives (4,8)(4, 8), and then undoing the translation by subtracting 66 from the xx-coordinate and 55 from the yy-coordinate yields (2,3)(-2, 3).
The correct answer is (2,3)(-2, 3) because we can find the starting position by working backward from the final position. The last transformation applied was a reflection across the yy-axis. Undoing this reflection maps the final coordinates (4,8)(-4, 8) to (4,8)(4, 8) because reflecting across the yy-axis changes the sign of the xx-coordinate. The first transformation was a translation of 66 units to the right and 55 units up. To undo this translation, we subtract 66 from the xx-coordinate and subtract 55 from the yy-coordinate of (4,8)(4, 8), giving (46,85)=(2,3)(4 - 6, 8 - 5) = (-2, 3).

Adım Adım Çözüm

1
Identify the final transformation and undo it. The final transformation is a reflection across the yy-axis, which maps (x,y)(x,y)(x, y) \rightarrow (-x, y).
The coordinates before reflection are (4,8)(4, 8).
Undoing a reflection across the yy-axis on (4,8)(-4, 8) means changing the sign of the xx-coordinate: (4)=4-(-4) = 4, while keeping the yy-coordinate the same.
2
Identify the first transformation and undo it. The first transformation is a translation of 66 units right and 55 units up, which maps (x,y)(x+6,y+5)(x, y) \rightarrow (x+6, y+5).
The starting coordinates PP are (2,3)(-2, 3).
To undo the translation, subtract 66 from the xx-coordinate and 55 from the yy-coordinate of the intermediate point (4,8)(4, 8): 46=24 - 6 = -2 and 85=38 - 5 = 3.

Anahtar Kavram

Transformations in the Coordinate Plane

Alternatif Yöntem

Instead of working backward, you can test the options by applying the transformations forward. For (2,3)(-2, 3), translating 6 units right and 5 units up gives (2+6,3+5)=(4,8)(-2+6, 3+5) = (4, 8). Reflecting across the yy-axis then gives (4,8)(-4, 8), which matches the final position.
Tahmini Süre:1m 15s
Soru 2345Soru

In a certain triangle, the ratio of the measure of the first angle to the measure of the second angle is 1:21:2. The measure of the third angle is 2020^\circ less than the measure of the second angle. What is the measure of the largest angle in the triangle?

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Cevap: 8080^\circ

Cevap

8080^\circ
The correct answer is 8080^\circ. By representing the first angle as xx, the second angle is 2x2x, and the third angle is 2x202x - 20. The sum of the interior angles in a triangle is always 180180^\circ, which gives the equation x+2x+(2x20)=180x + 2x + (2x - 20) = 180. Simplifying this results in 5x20=1805x - 20 = 180, which yields 5x=2005x = 200 and x=40x = 40. Substituting this value back into the expressions for the three angles gives measures of 4040^\circ, 8080^\circ, and 6060^\circ. Comparing these values shows that the largest angle is 8080^\circ.

Adım Adım Çözüm

1
Define the measures of the first and second angles using a single variable based on their ratio.
Let the first angle be xx and the second angle be 2x2x.
Since the ratio of the first angle to the second angle is 1:21:2, we can represent them as xx and 2x2x respectively.
2
Express the measure of the third angle in terms of the same variable.
The third angle is 2x202x - 20.
The problem states the third angle is 2020^\circ less than the second angle, which has a measure of 2x2x.
3
Set up an equation using the triangle angle sum theorem and solve for xx.
x+2x+(2x20)=180    5x20=180    5x=200    x=40x + 2x + (2x - 20) = 180 \implies 5x - 20 = 180 \implies 5x = 200 \implies x = 40.
The sum of the measures of the interior angles of any triangle is always 180180^\circ.
4
Calculate the measures of all three angles to determine which is the largest.
First angle = 4040^\circ, Second angle = 2(40)=802(40^\circ) = 80^\circ, Third angle = 2(40)20=602(40^\circ) - 20^\circ = 60^\circ. The largest angle is 8080^\circ.
We must substitute x=40x = 40 back into our expressions for each angle to find their actual degree measures and identify the largest one.

Anahtar Kavram

The interior angles of a triangle always sum to 180180^\circ. Ratios and word problems can be modeled algebraically to determine unknown angle measures.
Tahmini Süre:1m 15s
Soru 2346Soru

In the standard (x,y)(x, y) coordinate plane, a line LL passes through the points (a,a2)(a, a^2) and (b,b2)(b, b^2), where aa and bb are distinct real numbers. The slope of line LL is 88. If the midpoint of the line segment connecting these two points lies on the line y=5x1y = 5x - 1, what is the yy-coordinate of this midpoint?

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Cevap: 19

Cevap

The yy-coordinate of the midpoint is 1919.
Applying the slope formula to the points (a,a2)(a, a^2) and (b,b2)(b, b^2) yields \frac{b^2-a^2}{b-a} = a+b = 8. The xx-coordinate of the midpoint is \frac{a+b}{2} = 4. Substituting this value into the equation y=5x1y = 5x - 1 gives y=5(4)1=19y = 5(4) - 1 = 19.

Adım Adım Çözüm

1
Express the slope of line LL in terms of aa and bb and set it equal to the given slope.
a+b=8a + b = 8
The slope formula is m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1}. For the points (a,a2)(a, a^2) and (b,b2)(b, b^2), the slope is \frac{b^2 - a^2}{b - a}. Factoring the numerator gives \frac{(b-a)(b+a)}{b-a} = a + b. Since the slope is given as 88, we establish a+b=8a + b = 8.
2
Find the xx-coordinate of the midpoint of the segment connecting the two points.
xM=4x_M = 4
The midpoint formula for the xx-coordinate is xM=x1+x22x_M = \frac{x_1 + x_2}{2}. For our points, xM=a+b2x_M = \frac{a+b}{2}. Substituting the value a+b=8a+b = 8 gives xM=82=4x_M = \frac{8}{2} = 4.
3
Determine the yy-coordinate of the midpoint using the line equation.
yM=19y_M = 19
The midpoint lies on the line y=5x1y = 5x - 1. Substituting xM=4x_M = 4 into this equation gives yM=5(4)1=19y_M = 5(4) - 1 = 19.

Anahtar Kavram

Slope of a Line

Alternatif Yöntem

Let aa and bb be the real roots of the quadratic equation t28t+13=0t^2 - 8t + 13 = 0. By Vieta's formulas, a+b=8a+b = 8 and ab=13ab = 13. The xx-coordinate of the midpoint is \frac{a+b}{2} = 4, and the yy-coordinate is \frac{a^2+b^2}{2} = \frac{(a+b)^2 - 2ab}{2} = \frac{64 - 26}{2} = 19. Since the point (4,19)(4, 19) satisfies y=5x1y = 5x - 1, this confirms the existence of valid real coordinates (a,a2)(a, a^2) and (b,b2)(b, b^2) that produce the midpoint on the line.
Tahmini Süre:2m 0s
Soru 2347Soru

A municipal water reservoir is being drained at a constant rate. After 44 hours of draining, the reservoir contains 18,00018,000 gallons of water. After 77 hours of draining, it contains 13,50013,500 gallons of water. How many hours after the draining process begins will the reservoir be completely empty?

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Cevap: 16

Cevap

The reservoir will be completely empty 1616 hours after draining begins.
The correct answer is 1616 hours. The constant draining rate is calculated as the change in volume divided by the change in time: 13,50018,00074=1,500\frac{13,500 - 18,000}{7 - 4} = -1,500 gallons per hour. Since there are 18,00018,000 gallons left at the 44-hour mark, it will take an additional 18,0001,500=12\frac{18,000}{1,500} = 12 hours to completely empty the reservoir. The total time from the start is 4+12=164 + 12 = 16 hours.

Adım Adım Çözüm

1
Calculate the draining rate (the slope of the linear function).
The rate is 1,500-1,500 gallons per hour.
The rate of change is the change in volume divided by the change in time: 13,50018,00074=4,5003=1,500\frac{13,500 - 18,000}{7 - 4} = \frac{-4,500}{3} = -1,500 gallons per hour.
2
Determine the remaining time needed to empty the reservoir after the 77-hour mark.
It will take an additional 99 hours.
At 77 hours, the reservoir contains 13,50013,500 gallons. Draining at a rate of 1,5001,500 gallons per hour, the remaining time is 13,5001,500=9\frac{13,500}{1,500} = 9 hours.
3
Calculate the total elapsed time since the draining process began.
1616 hours
Adding the initial 77 hours of draining to the additional 99 hours needed gives 7+9=167 + 9 = 16 hours.

Anahtar Kavram

Linear word problems and finding intercepts

Alternatif Yöntem

We can model the volume of water WW as a linear function of time tt using the slope-intercept form W(t)=mt+bW(t) = mt + b. Substituting the rate m=1,500m = -1,500 and the point (4,18,000)(4, 18,000) gives 18,000=1,500(4)+b18,000 = -1,500(4) + b, which yields the yy-intercept (initial volume) b=24,000b = 24,000 gallons. The linear model is W(t)=1,500t+24,000W(t) = -1,500t + 24,000. Setting W(t)=0W(t) = 0 to find when the reservoir is empty gives 0=1,500t+24,0000 = -1,500t + 24,000, which simplifies to t=24,0001,500=16t = \frac{24,000}{1,500} = 16 hours.
Tahmini Süre:1m 30s
Soru 2348Soru

In ABC\triangle ABC, point DD lies on side BCBC. The segment ADAD divides the interior angle BAC\angle BAC into two angles, BAD\angle BAD and DAC\angle DAC, whose measures are in the ratio 3:23:2, respectively. The measures of the interior angles B\angle B and C\angle C are in the ratio 5:45:4, respectively. If the measure of ADC\angle ADC is 104104^\circ, what is the measure of BAC\angle BAC?

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Cevap: 9090^\circ

Cevap

9090^\circ
The correct answer is 9090^\circ. By expressing the angles in terms of variables using their ratios, we set up two independent linear equations: 3x+5y=1043x + 5y = 104 (from the exterior angle theorem on ABD\triangle ABD) and 2x+4y=762x + 4y = 76 (from the sum of angles in ADC\triangle ADC). Solving this system yields x=18x = 18. Since BAC\angle BAC is composed of BAD\angle BAD and DAC\angle DAC, its measure is 3x+2x=5x=5(18)=903x + 2x = 5x = 5(18^\circ) = 90^\circ.

Adım Adım Çözüm

1
Define variables for the partitioned angles and the base angles using the given ratios.
Let the measures of BAD\angle BAD and DAC\angle DAC be 3x3x and 2x2x respectively, so that BAC=5x\angle BAC = 5x. Let the measures of B\angle B and C\angle C be 5y5y and 4y4y respectively.
Ratios express quantities as multiples of a common variable, which simplifies setting up equations.
2
Apply the exterior angle theorem to ABD\triangle ABD at vertex DD.
The exterior angle ADC=BAD+B104=3x+5y\angle ADC = \angle BAD + \angle B \Rightarrow 104^\circ = 3x + 5y.
The measure of an exterior angle of a triangle is equal to the sum of the measures of its two remote interior angles.
3
Apply the angle sum theorem to ADC\triangle ADC.
DAC+C+ADC=1802x+4y+104=1802x+4y=76\angle DAC + \angle C + \angle ADC = 180^\circ \Rightarrow 2x + 4y + 104^\circ = 180^\circ \Rightarrow 2x + 4y = 76^\circ.
The sum of the measures of the interior angles of any triangle is always 180180^\circ.
4
Solve the system of linear equations: (1) 3x+5y=1043x + 5y = 104 and (2) 2x+4y=762x + 4y = 76.
Multiply equation (1) by 2 and equation (2) by 3 to align the coefficients of xx:
6x+10y=2086x + 10y = 208
6x+12y=2286x + 12y = 228
Subtract the first aligned equation from the second:
2y=20y=102y = 20 \Rightarrow y = 10.
Substitute y=10y = 10 back into equation (2):
2x+4(10)=762x=36x=182x + 4(10) = 76 \Rightarrow 2x = 36 \Rightarrow x = 18.
Solving the system of linear equations determines the values of the variables xx and yy.
5
Calculate the measure of BAC\angle BAC.
BAC=5x=5(18)=90\angle BAC = 5x = 5(18^\circ) = 90^\circ.
We defined the total measure of BAC\angle BAC as the sum of its two partitioned parts, 3x+2x=5x3x + 2x = 5x.

Anahtar Kavram

Using triangle angle properties and exterior angle theorems to set up and solve systems of linear equations.
Soru 2349Soru

In the standard (x,y)(x, y) coordinate plane, point PP is rotated 9090^\circ clockwise about the origin, and then translated 33 units to the left and 44 units up to form the image point P(1,2)P'(1, 2). What are the coordinates of the pre-image point PP?

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Cevap: (2,4)(2, 4)

Cevap

The coordinates of the pre-image point PP are (2,4)(2, 4).
To find the coordinates of the pre-image point, we must undo the transformations in reverse order. First, we undo the translation of 33 units left and 44 units up by translating the image point (1,2)(1, 2) by 33 units right and 44 units down, yielding the intermediate point (4,2)(4, -2). Next, we undo the 9090^\circ clockwise rotation by rotating this intermediate point 9090^\circ counterclockwise about the origin. Using the rotation rule (x,y)(y,x)(x, y) \rightarrow (-y, x) on (4,2)(4, -2) gives the pre-image point (2,4)(2, 4).

Adım Adım Çözüm

1
Identify the sequence of forward transformations and set up the path to work backward from the final image point P(1,2)P'(1, 2) to the pre-image point PP.
The forward sequence is: PRotate 90 clockwisePmidTranslate left 3, up 4P(1,2)P \xrightarrow{\text{Rotate } 90^\circ \text{ clockwise}} P_{\text{mid}} \xrightarrow{\text{Translate left 3, up 4}} P'(1, 2). To find PP, we must apply the inverse transformations in reverse order: P(1,2)Translate right 3, down 4PmidRotate 90 counterclockwisePP'(1, 2) \xrightarrow{\text{Translate right 3, down 4}} P_{\text{mid}} \xrightarrow{\text{Rotate } 90^\circ \text{ counterclockwise}} P.
Working backward with inverse operations is the standard mathematical procedure to retrieve a pre-image from its transformed image.
2
Apply the inverse translation to the image point P(1,2)P'(1, 2) to find the coordinates of the intermediate point PmidP_{\text{mid}}.
To undo a translation of 33 units left and 44 units up, translate 33 units right and 44 units down: x=1+3=4x = 1 + 3 = 4, and y=24=2y = 2 - 4 = -2. Thus, Pmid=(4,2)P_{\text{mid}} = (4, -2).
Applying the opposite direction and magnitude to the coordinates reverses the translation effect.
3
Apply the inverse rotation to the intermediate point Pmid(4,2)P_{\text{mid}}(4, -2) to find the coordinates of the pre-image point PP.
The inverse of a 9090^\circ clockwise rotation is a 9090^\circ counterclockwise rotation about the origin. The rule for a 9090^\circ counterclockwise rotation is (x,y)(y,x)(x, y) \rightarrow (-y, x). Applying this to (4,2)(4, -2) gives P((2),4)=P(2,4)P(-(-2), 4) = P(2, 4).
Rotating 9090^\circ counterclockwise reverses the initial 9090^\circ clockwise rotation, returning the point to its original pre-image coordinates.

Anahtar Kavram

Determining the coordinates of a pre-image by reversing a composite transformation in the coordinate plane.
Soru 2350Soru

A company's weekly revenue, R(x)R(x), and weekly cost, C(x)C(x), in dollars, are modeled by the functions R(x)=(2x2+3)2R(x) = (2x^2 + 3)^2 and C(x)=x2(x35)C(x) = x^2(x^3 - 5), where xx represents the number of units produced and sold. Which of the following expressions represents the company's weekly profit, P(x)=R(x)C(x)P(x) = R(x) - C(x)?

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Cevap: x5+4x4+17x2+9-x^5 + 4x^4 + 17x^2 + 9

Cevap

The expression representing the weekly profit is x5+4x4+17x2+9-x^5 + 4x^4 + 17x^2 + 9.
To find the profit function, we subtract the cost function from the revenue function. First, expanding (2x2+3)2(2x^2 + 3)^2 yields 4x4+12x2+94x^4 + 12x^2 + 9. Second, distributing x2x^2 over (x35)(x^3 - 5) yields x55x2x^5 - 5x^2. Subtracting these two functions gives (4x4+12x2+9)(x55x2)(4x^4 + 12x^2 + 9) - (x^5 - 5x^2). Distributing the subtraction sign changes the signs of the cost function to x5+5x2-x^5 + 5x^2. Combining like terms (12x2+5x2=17x212x^2 + 5x^2 = 17x^2) and organizing the expression in descending order yields x5+4x4+17x2+9-x^5 + 4x^4 + 17x^2 + 9.

Adım Adım Çözüm

1
Expand the revenue function R(x)=(2x2+3)2R(x) = (2x^2 + 3)^2 using the binomial square identity (a+b)2=a2+2ab+b2(a+b)^2 = a^2 + 2ab + b^2.
R(x)=(2x2)2+2(2x2)(3)+32=4x4+12x2+9R(x) = (2x^2)^2 + 2(2x^2)(3) + 3^2 = 4x^4 + 12x^2 + 9
This simplifies the revenue expression into a standard polynomial form.
2
Expand the cost function C(x)=x2(x35)C(x) = x^2(x^3 - 5) by distributing x2x^2 to both terms inside the parentheses and applying the product rule for exponents xaxb=xa+bx^a \cdot x^b = x^{a+b}.
C(x)=x2(x3)x2(5)=x55x2C(x) = x^2(x^3) - x^2(5) = x^5 - 5x^2
This simplifies the cost expression into a standard polynomial form.
3
Subtract C(x)C(x) from R(x)R(x) by setting up P(x)=R(x)C(x)P(x) = R(x) - C(x) and distributing the negative sign to all terms of C(x)C(x).
P(x)=(4x4+12x2+9)(x55x2)=4x4+12x2+9x5+5x2P(x) = (4x^4 + 12x^2 + 9) - (x^5 - 5x^2) = 4x^4 + 12x^2 + 9 - x^5 + 5x^2
Profit is revenue minus cost, and distributing the negative sign correctly is essential.
4
Combine like terms and write the final expression in descending order of exponents.
P(x)=x5+4x4+17x2+9P(x) = -x^5 + 4x^4 + 17x^2 + 9
To present the polynomial in standard form.

Anahtar Kavram

Polynomial operations, including expanding binomial squares, distributing monomial terms, and subtracting polynomials with careful attention to sign distribution.
Soru 2351Soru

A right triangle is plotted in the standard (x,y)(x, y) coordinate plane. The vertices of the triangle are located at (3,2)(-3, -2), (5,2)(5, -2), and (3,4)(-3, 4). What is the length of the hypotenuse of the triangle?

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Cevap: 1010

Cevap

10
The distance between the vertices (3,2)(-3, -2) and (5,2)(5, -2) along the horizontal line y=2y = -2 is 5(3)=85 - (-3) = 8 units. The distance between the vertices (3,2)(-3, -2) and (3,4)(-3, 4) along the vertical line x=3x = -3 is 4(2)=64 - (-2) = 6 units. Because horizontal and vertical segments meet at a right angle, they form the legs of a right triangle. Applying the Pythagorean theorem, the length of the hypotenuse is the square root of the sum of the squares of the legs: 82+62=64+36=100=10\sqrt{8^2 + 6^2} = \sqrt{64 + 36} = \sqrt{100} = 10.

Adım Adım Çözüm

1
Determine the lengths of the two perpendicular legs of the right triangle on the coordinate plane.
The horizontal leg has a length of 5(3)=85 - (-3) = 8 units, and the vertical leg has a length of 4(2)=64 - (-2) = 6 units.
Because the segment between (3,2)(-3, -2) and (5,2)(5, -2) is horizontal (constant y=2y = -2) and the segment between (3,2)(-3, -2) and (3,4)(-3, 4) is vertical (constant x=3x = -3).
2
Apply the Pythagorean theorem to calculate the length of the hypotenuse.
The hypotenuse length is 82+62=64+36=100=10\sqrt{8^2 + 6^2} = \sqrt{64 + 36} = \sqrt{100} = 10 units.
The Pythagorean theorem states that for any right triangle with legs aa and bb and hypotenuse cc, a2+b2=c2a^2 + b^2 = c^2.

Anahtar Kavram

Finding the lengths of segments and applying the Pythagorean theorem on the coordinate plane.
Soru 2352Soru

The ratio of the number of students in a school's science club to the number of students in its art club is 3:53:5. There are 88 more students in the art club than in the science club. If xx students from the art club leave to join the science club, the ratio of the number of science club members to the number of art club members becomes 3:13:1. What is the value of xx?

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Cevap: 12

Cevap

12
The correct answer is 12. Let the initial number of students in the science and art clubs be 3k3k and 5k5k, respectively. Since there are 8 more students in the art club, we set up the equation 5k=3k+85k = 3k + 8, which simplifies to 2k=82k = 8, giving k=4k = 4. This means there are initially 12 science club members and 20 art club members. When xx students transfer from the art club to the science club, the new sizes are 12+x12 + x and 20x20 - x. Setting up the new ratio gives 12+x20x=3\frac{12 + x}{20 - x} = 3. Solving this equation yields 12+x=603x12 + x = 60 - 3x, which simplifies to 4x=484x = 48, resulting in x=12x = 12.

Adım Adım Çözüm

1
Represent the initial number of students in each club using the given ratio.
Let the number of science club members be 3k3k and the number of art club members be 5k5k, where kk is a positive constant.
The ratio of science club members to art club members is 3:53:5.
2
Set up and solve a linear equation to find the value of kk and the starting number of members in each club.
5k=3k+82k=8k=45k = 3k + 8 \Rightarrow 2k = 8 \Rightarrow k = 4. Thus, the science club has 3(4)=123(4) = 12 members and the art club has 5(4)=205(4) = 20 members.
There are 88 more students in the art club than in the science club, so the difference between the two groups is 88.
3
Write the new member counts after xx students transfer and set up the ratio equation.
The new science club size is 12+x12 + x and the new art club size is 20x20 - x. The new ratio equation is 12+x20x=31\frac{12 + x}{20 - x} = \frac{3}{1}.
The xx students leave the art club (subtracting xx) and join the science club (adding xx), resulting in a new ratio of 3:13:1.
4
Solve the rational equation for xx.
12+x=3(20x)12+x=603x4x=48x=1212 + x = 3(20 - x) \Rightarrow 12 + x = 60 - 3x \Rightarrow 4x = 48 \Rightarrow x = 12.
Cross-multiplying and isolating xx yields the number of students who transferred.

Anahtar Kavram

Translating verbal statements involving ratios and changes in quantities into solvable linear algebraic equations.
Tahmini Süre:1m 30s
Soru 2353Soru

A geometric sequence has a first term of 232^3 and a common ratio of 222^2. What is the value of the 5th term of this sequence?

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Cevap: 2,0482,048

Cevap

The 5th term of the geometric sequence is 2,0482,048.
To find the 5th term of a geometric sequence, we use the formula an=a1rn1a_n = a_1 \cdot r^{n-1}. Substituting the given first term a1=23=8a_1 = 2^3 = 8 and the common ratio r=22=4r = 2^2 = 4 for n=5n = 5 gives a5=23(22)4a_5 = 2^3 \cdot (2^2)^4. Applying the power of a power rule, (22)4=22×4=28(2^2)^4 = 2^{2 \times 4} = 2^8. Then, multiplying the bases by adding the exponents gives 2328=23+8=2112^3 \cdot 2^8 = 2^{3+8} = 2^{11}, which evaluates to 2,0482,048.

Adım Adım Çözüm

1
Identify the given values and the formula for the nn-th term of a geometric sequence.
The first term is a1=23=8a_1 = 2^3 = 8, the common ratio is r=22=4r = 2^2 = 4, and we need to find the term for n=5n = 5 using the formula an=a1rn1a_n = a_1 \cdot r^{n-1}.
Knowing the correct formula is necessary to compute the specific term of a geometric sequence.
2
Substitute the values into the formula to express the 5th term in terms of base 2.
a5=23(22)51=23(22)4a_5 = 2^3 \cdot (2^2)^{5-1} = 2^3 \cdot (2^2)^4
This substitutes the specific term number and sequence parameters into the general term formula.
3
Simplify the exponential expression and calculate the final numerical value.
a5=2328=23+8=211=2,048a_5 = 2^3 \cdot 2^8 = 2^{3+8} = 2^{11} = 2,048
Applying exponent rules (multiplying powers of a power and adding exponents when multiplying like bases) allows us to evaluate the expression to a single number.

Anahtar Kavram

Finding a specific term in a geometric sequence using exponential properties
Tahmini Süre:1m 0s
Soru 2354Soru

A circle in the standard (x,y)(x,y) coordinate plane is defined by the equation (x+3)2+(y4)2=25(x + 3)^2 + (y - 4)^2 = 25. What are the coordinates of the center and the length of the radius of this circle?

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Cevap: Center: (3,4)(-3, 4); Radius: 55

Cevap

Center: (3,4)(-3, 4); Radius: 55
The standard form of a circle's equation is (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2, where the center is (h,k)(h, k) and the radius is rr. Matching (x+3)2+(y4)2=25(x + 3)^2 + (y - 4)^2 = 25 to this standard form, we find h=3h = -3, k=4k = 4, and r2=25r^2 = 25 (which gives r=5r = 5). Therefore, the center is (3,4)(-3, 4) and the radius is 55.

Adım Adım Çözüm

1
Identify the standard form of a circle's equation.
The standard equation of a circle with center (h,k)(h, k) and radius rr is (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2.
This formula provides the template to match the given equation and extract the parameters.
2
Rewrite the given equation (x+3)2+(y4)2=25(x + 3)^2 + (y - 4)^2 = 25 to match the signs and exponents of the standard form.
The equation can be written as (x(3))2+(y4)2=52(x - (-3))^2 + (y - 4)^2 = 5^2.
Rewriting the terms helps to identify the exact values of hh, kk, and rr without sign confusion.
3
Extract the center (h,k)(h, k) and radius rr from the rewritten equation.
Comparing the terms shows h=3h = -3, k=4k = 4, and r=5r = 5, giving a center of (3,4)(-3, 4) and a radius of 55.
These extracted values are the final answer.

Anahtar Kavram

Equations and Graphs of Circles
Soru 2355Soru

A parabola is defined by the equation y=x24x+3y = x^2 - 4x + 3, and a line is defined by the equation y=x+7y = -x + 7. The parabola and the line intersect at two points in the standard (x,y)(x, y) coordinate plane. What is the distance between these two points of intersection?

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Cevap: 525\sqrt{2}

Cevap

525\sqrt{2}
The correct answer is the value representing the straight-line distance between the two intersection points. Setting the equations equal to each other gives x23x4=0x^2 - 3x - 4 = 0, which factors to (x4)(x+1)=0(x - 4)(x + 1) = 0. This yields x=4x = 4 and x=1x = -1. Evaluating these in y=x+7y = -x + 7 yields the points (4,3)(4, 3) and (1,8)(-1, 8). The distance between them is (4(1))2+(38)2=25+25=50=52\sqrt{(4 - (-1))^2 + (3 - 8)^2} = \sqrt{25 + 25} = \sqrt{50} = 5\sqrt{2}.

Adım Adım Çözüm

1
Set the equations of the parabola and line equal to each other to find the xx-coordinates of the intersection points.
x24x+3=x+7x^2 - 4x + 3 = -x + 7
Intersection points must satisfy both equations simultaneously.
2
Rearrange the equation into standard quadratic form and factor it to solve for xx.
x23x4=0    (x4)(x+1)=0    x=4x^2 - 3x - 4 = 0 \implies (x - 4)(x + 1) = 0 \implies x = 4 or x=1x = -1
Factoring the quadratic equation gives the roots which correspond to the xx-coordinates of the intersection points.
3
Substitute the xx-values back into the linear equation to determine the corresponding yy-coordinates.
For x=4x = 4, y=(4)+7=3y = -(4) + 7 = 3, yielding point (4,3)(4, 3). For x=1x = -1, y=(1)+7=8y = -(-1) + 7 = 8, yielding point (1,8)(-1, 8).
Substituting into the simpler linear equation provides the yy-coordinates of the intersection points.
4
Apply the distance formula to calculate the distance between (4,3)(4, 3) and (1,8)(-1, 8).
d=(4(1))2+(38)2=52+(5)2=25+25=50=52d = \sqrt{(4 - (-1))^2 + (3 - 8)^2} = \sqrt{5^2 + (-5)^2} = \sqrt{25 + 25} = \sqrt{50} = 5\sqrt{2}
The distance formula calculates the straight-line distance between two coordinates in the coordinate plane.

Anahtar Kavram

Systems of Linear and Non-Linear Equations
Soru 2356Soru

A recipe calls for 12\frac{1}{2} cup of sugar on the first day of a fermentation process. Each day after that, the ratio of the sugar added on that day to the sugar added on the previous day is 1:31:3. What is the total amount of sugar, in cups, added during the first 3 days?

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Cevap: 1318\frac{13}{18}

Cevap

The total amount of sugar added is 1318\frac{13}{18} cups.
The correct answer is 1318\frac{13}{18}. The sugar added on Day 1 is 12\frac{1}{2} cup. Since the ratio between consecutive days is 1:31:3, the common ratio is r=13r = \frac{1}{3}. This gives a Day 2 amount of 12×13=16\frac{1}{2} \times \frac{1}{3} = \frac{1}{6} cup, and a Day 3 amount of 16×13=118\frac{1}{6} \times \frac{1}{3} = \frac{1}{18} cup. Summing these three amounts using a common denominator of 18 yields 918+318+118=1318\frac{9}{18} + \frac{3}{18} + \frac{1}{18} = \frac{13}{18} cups.

Adım Adım Çözüm

1
Identify the type of sequence and the first term.
The first term is a1=12a_1 = \frac{1}{2}. The sequence is geometric because the ratio between the amounts added on consecutive days is constant.
The problem states that the ratio of sugar added on consecutive days is 1:31:3, which establishes a common ratio for a geometric sequence.
2
Determine the common ratio and find the terms for the second and third days.
The common ratio is r=13r = \frac{1}{3}. The second term is a2=12×13=16a_2 = \frac{1}{2} \times \frac{1}{3} = \frac{1}{6}, and the third term is a3=16×13=118a_3 = \frac{1}{6} \times \frac{1}{3} = \frac{1}{18}.
Each subsequent term of a geometric sequence is found by multiplying the previous term by the common ratio.
3
Calculate the sum of the first three terms.
The total sum is S3=12+16+118=918+318+118=1318S_3 = \frac{1}{2} + \frac{1}{6} + \frac{1}{18} = \frac{9}{18} + \frac{3}{18} + \frac{1}{18} = \frac{13}{18}.
Finding the total amount requires summing the individual amounts added over the three days using a common denominator of 18.

Anahtar Kavram

Sum of a finite geometric series

Alternatif Yöntem

Instead of calculating and adding the individual terms, you can use the sum of a finite geometric series formula: Sn=a1(1rn)1rS_n = \frac{a_1(1-r^n)}{1-r}. Substituting a1=12a_1 = \frac{1}{2}, r=13r = \frac{1}{3}, and n=3n=3 yields: S3=12(1(13)3)113=12(1127)23=12(2627)23=1327×32=1318S_3 = \frac{\frac{1}{2}\left(1 - \left(\frac{1}{3}\right)^3\right)}{1 - \frac{1}{3}} = \frac{\frac{1}{2}\left(1 - \frac{1}{27}\right)}{\frac{2}{3}} = \frac{\frac{1}{2}\left(\frac{26}{27}\right)}{\frac{2}{3}} = \frac{13}{27} \times \frac{3}{2} = \frac{13}{18}.
Tahmini Süre:1m 30s
Soru 2357Soru

A circle in the standard (x,y)(x, y) coordinate plane is defined by the equation (x9)2+(y+4)2=81(x - 9)^2 + (y + 4)^2 = 81. What is the radius of this circle?

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Cevap: 9

Cevap

The radius of the circle is 9.
The standard equation of a circle in the coordinate plane is (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2, where rr is the radius. For the equation (x9)2+(y+4)2=81(x - 9)^2 + (y + 4)^2 = 81, the right-hand side represents r2r^2, so r2=81r^2 = 81. Taking the positive square root of both sides gives r=81=9r = \sqrt{81} = 9.

Adım Adım Çözüm

1
Identify the standard form of the circle equation.
The standard equation of a circle is (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2, where (h,k)(h, k) is the center and rr is the radius.
This allows us to relate the terms of the given equation to the components of the circle.
2
Match the given equation to the standard form.
By comparing (x9)2+(y+4)2=81(x - 9)^2 + (y + 4)^2 = 81 to (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2, we find that r2=81r^2 = 81.
The constant on the right side of the standard equation represents the square of the radius.
3
Solve for the radius rr.
r=81=9r = \sqrt{81} = 9.
Taking the square root of r2r^2 gives the actual radius of the circle.

Anahtar Kavram

Identifying the radius from the standard equation of a circle
Soru 2358Soru

An artist is designing a rectangular stained-glass window. The total area of the window, in square inches, is represented by the polynomial 8x2+2x38x^2 + 2x - 3. The area of the central blue glass section, in square inches, is represented by the product (2x3)(x2)(2x - 3)(x - 2). The remaining portion of the window is made of clear glass. Which of the following expressions represents the area, in square inches, of the clear glass section?

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Cevap: 6x2+9x96x^2 + 9x - 9

Cevap

The expression representing the area of the clear glass section is 6x2+9x96x^2 + 9x - 9.
The correct expression is 6x2+9x96x^2 + 9x - 9. The area of the clear glass is found by expanding (2x3)(x2)(2x - 3)(x - 2) to get 2x27x+62x^2 - 7x + 6 and then subtracting this from the total area: (8x2+2x3)(2x27x+6)=8x2+2x32x2+7x6=6x2+9x9(8x^2 + 2x - 3) - (2x^2 - 7x + 6) = 8x^2 + 2x - 3 - 2x^2 + 7x - 6 = 6x^2 + 9x - 9.

Adım Adım Çözüm

1
Expand the product representing the area of the blue glass section using binomial multiplication.
(2x3)(x2)=2x24x3x+6=2x27x+6(2x - 3)(x - 2) = 2x^2 - 4x - 3x + 6 = 2x^2 - 7x + 6
Converting the factored area of the blue glass section to standard form is necessary before subtraction.
2
Set up the subtraction of the blue glass area from the total area.
(8x2+2x3)(2x27x+6)(8x^2 + 2x - 3) - (2x^2 - 7x + 6)
The clear glass area is found by subtracting the blue glass area from the total window area.
3
Distribute the negative sign to each term of the second polynomial and combine like terms.
8x2+2x32x2+7x6=(8x22x2)+(2x+7x)+(36)=6x2+9x98x^2 + 2x - 3 - 2x^2 + 7x - 6 = (8x^2 - 2x^2) + (2x + 7x) + (-3 - 6) = 6x^2 + 9x - 9
Distributing the subtraction sign changes the signs of all terms inside the second set of parentheses, allowing for correct simplification.

Anahtar Kavram

Operations on Polynomials
Tahmini Süre:1m 30s
Soru 2359Soru

A rectangular garden has a straight walking path that connects two opposite corners. The length of the path is 170170 meters, and the width of the garden is 8080 meters. What is the length, in meters, of the garden?

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Cevap: 150

Cevap

The length of the garden is 150150 meters.
The diagonal path, width, and length of the rectangular garden form a right triangle where the path is the hypotenuse. According to the Pythagorean theorem, the square of the length plus the square of the width equals the square of the path: length2+802=1702\text{length}^2 + 80^2 = 170^2. This simplifies to length2+6,400=28,900\text{length}^2 + 6,400 = 28,900. Subtracting 6,4006,400 from both sides gives length2=22,500\text{length}^2 = 22,500. Taking the square root of 22,50022,500 yields 150150 meters.

Adım Adım Çözüm

1
Identify the right triangle formed by the length, width, and diagonal path of the garden.
The width (8080 meters) and the unknown length are the legs, while the diagonal path (170170 meters) is the hypotenuse.
The diagonal of a rectangle forms two congruent right triangles with the rectangle's sides.
2
Set up the Pythagorean equation to solve for the unknown leg.
length2+802=1702\text{length}^2 + 80^2 = 170^2
The Pythagorean theorem states that a2+b2=c2a^2 + b^2 = c^2, where cc is the hypotenuse.
3
Calculate the squares of the known lengths.
802=6,40080^2 = 6,400 and 1702=28,900170^2 = 28,900
Evaluate the exponents to simplify the equation.
4
Isolate the squared unknown variable.
length2=28,9006,400=22,500\text{length}^2 = 28,900 - 6,400 = 22,500
Subtract 6,4006,400 from both sides of the equation.
5
Take the square root of both sides to find the length.
length=22,500=150\text{length} = \sqrt{22,500} = 150
The square root operation reverses the squaring of the variable.

Anahtar Kavram

Applying the Pythagorean theorem to find the length of an unknown leg in a right triangle.
Tahmini Süre:1m 0s
Soru 2360Soru

In the standard (x,y)(x, y) coordinate plane, the midpoint of a line segment with endpoints (1,2)(1, -2) and (7,10)(7, 10) is the center of a circle. If the point (8,7)(8, 7) lies on the circle, what is the radius of the circle?

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Cevap: 5

Cevap

The radius of the circle is 5.
The midpoint of the line segment with endpoints (1,2)(1, -2) and (7,10)(7, 10) is calculated as (1+72,2+102)=(4,4)(\frac{1+7}{2}, \frac{-2+10}{2}) = (4, 4), which is the center of the circle. The distance from the center (4,4)(4, 4) to the point (8,7)(8, 7) on the circle is the radius, which is (84)2+(74)2=16+9=5\sqrt{(8-4)^2 + (7-4)^2} = \sqrt{16+9} = 5.

Adım Adım Çözüm

1
Find the midpoint of the line segment with endpoints (1,2)(1, -2) and (7,10)(7, 10) to determine the center of the circle.
The center of the circle is (4,4)(4, 4).
The midpoint of a segment with endpoints (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2) is given by (x1+x22,y1+y22)(\frac{x_1+x_2}{2}, \frac{y_1+y_2}{2}). Calculating this gives (1+72,2+102)=(4,4)(\frac{1+7}{2}, \frac{-2+10}{2}) = (4, 4).
2
Calculate the distance between the center of the circle (4,4)(4, 4) and the point (8,7)(8, 7) on the circle to find the radius.
The radius of the circle is 5.
The distance formula is d=(x2x1)2+(y2y1)2d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}. Substituting the coordinates gives (84)2+(74)2=42+32=16+9=25=5\sqrt{(8-4)^2 + (7-4)^2} = \sqrt{4^2 + 3^2} = \sqrt{16+9} = \sqrt{25} = 5.

Anahtar Kavram

Finding the midpoint of a line segment to determine a circle's center and using the distance formula to calculate its radius.
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