Tüm alıştırma soruları

5556 soru

Soru 2181Soru

In the standard (x,y)(x,y) coordinate plane, a triangle has vertices at A(2,4)A(2, 4), B(6,4)B(6, 4), and C(2,10)C(2, 10). The triangle undergoes a series of transformations: first, it is reflected across the line y=xy = x; next, the resulting image is dilated by a scale factor of 12\frac{1}{2} with the center of dilation at (2,2)(2, 2); finally, this image is translated 11 unit to the left and 33 units down. What are the coordinates of the final image of vertex CC?

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Cevap: (5,1)(5, -1)

Cevap

(5,1)(5, -1)
The correct answer is (5,1)(5, -1) because applying the three transformations sequentially yields the correct final coordinates: first, reflecting C(2,10)C(2, 10) across the line y=xy = x gives C(10,2)C'(10, 2); second, dilating C(10,2)C'(10, 2) by a scale factor of 12\frac{1}{2} centered at (2,2)(2, 2) gives C(6,2)C''(6, 2); and finally, translating C(6,2)C''(6, 2) by 11 unit left and 33 units down results in (5,1)(5, -1).

Adım Adım Çözüm

1
Reflect the initial coordinates of vertex C(2,10)C(2, 10) across the line y=xy = x.
C(10,2)C'(10, 2)
Reflecting a point (x,y)(x, y) across the line y=xy = x interchanges the coordinates, mapping (x,y)(x, y) to (y,x)(y, x).
2
Dilate the point C(10,2)C'(10, 2) by a scale factor of k=12k = \frac{1}{2} centered at P(2,2)P(2, 2).
C(6,2)C''(6, 2)
The formula for a dilation centered at (a,b)(a, b) is (x,y)=(a+k(xa),b+k(yb))(x'', y'') = (a + k(x' - a), b + k(y' - b)). Substituting a=2,b=2,k=12,x=10,y=2a=2, b=2, k=\frac{1}{2}, x'=10, y'=2 gives (2+12(102),2+12(22))=(2+4,2+0)=(6,2)(2 + \frac{1}{2}(10-2), 2 + \frac{1}{2}(2-2)) = (2+4, 2+0) = (6, 2).
3
Translate the point C(6,2)C''(6, 2) by 11 unit to the left and 33 units down.
C(5,1)C'''(5, -1)
Translating 11 unit left subtracts 11 from the xx-coordinate (61=56 - 1 = 5), and translating 33 units down subtracts 33 from the yy-coordinate (23=12 - 3 = -1).

Anahtar Kavram

Composite transformations in the coordinate plane involving reflections, dilations with non-origin centers, and translations.
Tahmini Süre:2m 0s
Soru 2182Soru

In the standard (x,y)(x, y) coordinate plane, a line with a negative slope passes through the point (4,3)(4, 3) and has an xx-intercept that is twice its yy-intercept. If the equation of this line is written in the form Ax+By=CAx + By = C, where AA, BB, and CC are integers with no common factor greater than 1, and A>0A > 0, what is the value of CC?

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Cevap: 10

Cevap

The value of CC is 10.
The correct answer is 10. By setting the intercepts as (2b,0)(2b, 0) and (0,b)(0, b), we find the slope is m=12m = -\frac{1}{2}. Applying the point-slope formula with (4,3)(4, 3) gives y3=12(x4)y - 3 = -\frac{1}{2}(x - 4), which simplifies to y=12x+5y = -\frac{1}{2}x + 5. Converting this to standard form with A>0A > 0 yields x+2y=10x + 2y = 10, where C=10C = 10.

Adım Adım Çözüm

1
Represent the coordinates of the intercepts using a variable.
The yy-intercept is (0,b)(0, b) and the xx-intercept is (2b,0)(2b, 0).
The problem states that the xx-intercept is twice the yy-intercept.
2
Calculate the slope (mm) of the line using the intercepts.
m=b002b=12m = \frac{b - 0}{0 - 2b} = -\frac{1}{2}
The slope of a line passing through (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2) is given by m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1}.
3
Find the equation of the line using the point-slope form with point (4,3)(4, 3).
y3=12(x4)y=12x+5y - 3 = -\frac{1}{2}(x - 4) \Rightarrow y = -\frac{1}{2}x + 5
The point-slope form of a linear equation is yy1=m(xx1)y - y_1 = m(x - x_1).
4
Convert the equation to the standard form Ax+By=CAx + By = C.
x+2y=10x + 2y = 10
Multiplying the equation by 2 and moving the xx term to the left side results in integer coefficients where the coefficient of xx is positive (A=1>0A = 1 > 0).
5
Identify the value of CC from the standard form equation.
C=10C = 10
Comparing x+2y=10x + 2y = 10 with Ax+By=CAx + By = C shows that A=1A=1, B=2B=2, and C=10C=10. These integers share no common factors greater than 1.

Anahtar Kavram

Converting a linear equation to standard form using given geometric features and a coordinate point.

Alternatif Yöntem

Instead of using the point-slope formula, substitute the point (4,3)(4, 3) directly into the intercept form of a linear equation, xa+yb=1\frac{x}{a} + \frac{y}{b} = 1. Since a=2ba = 2b, this becomes 42b+3b=1\frac{4}{2b} + \frac{3}{b} = 1. Simplifying this gives 2b+3b=15b=1b=5\frac{2}{b} + \frac{3}{b} = 1 \Rightarrow \frac{5}{b} = 1 \Rightarrow b = 5. Thus, a=10a = 10. The intercept form is x10+y5=1\frac{x}{10} + \frac{y}{5} = 1. Multiplying by 10 to clear denominators gives x+2y=10x + 2y = 10, where C=10C = 10.
Tahmini Süre:1m 30s
Soru 2183Soru

In the standard (x,y)(x, y) coordinate plane, the perpendicular bisector of the line segment with endpoints (1,2)(1, 2) and (5,10)(5, 10) intersects the curve y=x2y = x^2 at two points. If one of these intersection points lies in the second quadrant, what is the yy-coordinate of this point?

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Cevap: 9

Cevap

The correct answer is 99.
The perpendicular bisector of the segment connecting (1,2)(1, 2) and (5,10)(5, 10) passes through their midpoint (3,6)(3, 6) and has a slope of 12-\frac{1}{2} (the negative reciprocal of 22). The equation of this line is x+2y=15x + 2y = 15. Substituting y=x2y = x^2 yields the quadratic equation 2x2+x15=02x^2 + x - 15 = 0, which factors into (2x5)(x+3)=0(2x - 5)(x + 3) = 0. The solution in the second quadrant corresponds to the negative xx-coordinate, x=3x = -3. Squaring this value gives a yy-coordinate of 99.

Adım Adım Çözüm

1
Find the midpoint of the segment with endpoints (1,2)(1, 2) and (5,10)(5, 10).
The midpoint is (3,6)(3, 6).
The perpendicular bisector of a segment passes through its midpoint.
2
Calculate the slope of the segment and the slope of the perpendicular bisector.
The slope of the segment is 22, and the perpendicular slope is 12-\frac{1}{2}.
Perpendicular lines have slopes that are negative reciprocals of each other.
3
Write the equation of the perpendicular bisector.
The equation of the line is x+2y=15x + 2y = 15.
Using the point-slope form with point (3,6)(3, 6) and slope 12-\frac{1}{2} yields y6=12(x3)y - 6 = -\frac{1}{2}(x - 3), which simplifies to x+2y=15x + 2y = 15.
4
Find the intersection points of the line and the curve y=x2y = x^2.
The xx-coordinates of the intersection points are 2.52.5 and 3-3.
Substituting y=x2y = x^2 into x+2y=15x + 2y = 15 gives the quadratic equation 2x2+x15=02x^2 + x - 15 = 0, which factors as (2x5)(x+3)=0(2x - 5)(x + 3) = 0.
5
Identify the point in the second quadrant and find its yy-coordinate.
The point is (3,9)(-3, 9), so the yy-coordinate is 99.
A point in the second quadrant must have a negative xx-coordinate (x=3x = -3) and a positive yy-coordinate (y=9y = 9).

Anahtar Kavram

Perpendicular bisectors and systems of linear-quadratic equations in coordinate geometry
Soru 2184Soru

A delivery drone starts a flight with a battery charge of 95%95\%. The battery charge decreases at a constant rate of 1.5%1.5\% per minute of flight time. During the flight, the drone lands on a charging station for 1515 minutes, during which its battery charge increases at a constant rate of 2.4%2.4\% per minute. After this charging period, the drone resumes its flight. If the drone ends its flight with a battery charge of 65%65\%, and its total flight time (excluding the time spent charging) was tt minutes, what is the value of tt?

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Cevap: 44

Cevap

44
The correct answer is found by setting up a linear equation that models the drone's battery charge changes. The drone starts with 95%95\% battery, loses 1.5%1.5\% per minute for tt minutes, and gains 36%36\% from charging (15×2.4%15 \times 2.4\%). Setting this equal to the final charge of 65%65\% gives the equation 951.5t+36=6595 - 1.5t + 36 = 65. Simplifying gives 1311.5t=65131 - 1.5t = 65, which leads to 1.5t=66-1.5t = -66 and t=44t = 44.

Adım Adım Çözüm

1
Calculate the total percentage of battery charge gained while charging.
36%36\%
The drone charges at a rate of 2.4%2.4\% per minute for 1515 minutes, so the total gain is 15×2.4%=36%15 \times 2.4\% = 36\%.
2
Set up a linear equation for the final battery charge.
951.5t+36=6595 - 1.5t + 36 = 65
The final battery charge (65%65\%) is the initial charge (95%95\%) minus the battery consumed during flight (1.5%1.5\% per minute for tt minutes) plus the charge gained (36%36\%).
3
Combine constant terms on the left side of the equation.
1311.5t=65131 - 1.5t = 65
Adding 9595 and 3636 simplifies the expression on the left side.
4
Isolate the variable term by subtracting 131131 from both sides.
1.5t=66-1.5t = -66
Subtracting 131131 from both sides leaves only the variable term on the left.
5
Divide both sides by 1.5-1.5 to solve for tt.
t=44t = 44
Dividing 66-66 by 1.5-1.5 isolates tt to find the total flight time.

Anahtar Kavram

Solving linear equations in a real-world context by setting up an algebraic equation.
Tahmini Süre:1m 30s
Soru 2185Soru

What is the complete solution set for the inequality 73n<11|7 - 3n| < 11?

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Cevap: 43<n<6-\frac{4}{3} < n < 6

Cevap

43<n<6-\frac{4}{3} < n < 6
To solve 73n<11|7 - 3n| < 11, rewrite it as the compound inequality 11<73n<11-11 < 7 - 3n < 11. Subtracting 77 from all parts yields 18<3n<4-18 < -3n < 4. Finally, dividing by 3-3 and reversing the inequality signs gives 6>n>436 > n > -\frac{4}{3}, which simplifies to the interval 43<n<6-\frac{4}{3} < n < 6. This matches the correct option.

Adım Adım Çözüm

1
Express the absolute value inequality as a compound inequality.
11<73n<11-11 < 7 - 3n < 11
An absolute value inequality of the form u<c|u| < c is equivalent to the compound inequality c<u<c-c < u < c.
2
Subtract 77 from all three parts of the inequality.
18<3n<4-18 < -3n < 4
To isolate the term containing nn, we subtract 77 from all parts of the inequality.
3
Divide all three parts by 3-3 and reverse the inequality signs.
6>n>436 > n > -\frac{4}{3}, which is equivalent to 43<n<6-\frac{4}{3} < n < 6
Dividing an inequality by a negative number requires reversing the direction of the inequality signs to maintain a true statement.

Anahtar Kavram

Absolute Value Equations and Inequalities
Soru 2186Soru

In PQR\triangle PQR, the lengths of sides PQPQ and PRPR are equal. If the measure of P\angle P is 7070^\circ, what is the measure, in degrees, of Q\angle Q?

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Cevap: 55

Cevap

The measure of Q\angle Q is 5555^\circ.
Since PQ=PRPQ = PR, PQR\triangle PQR is an isosceles triangle with base QRQR, which means the base angles Q\angle Q and R\angle R have equal measures. The sum of the interior angles of a triangle is 180180^\circ. Setting up the equation gives 70+2(Q)=18070^\circ + 2(\angle Q) = 180^\circ. Subtracting 7070^\circ from both sides yields 2(Q)=1102(\angle Q) = 110^\circ. Dividing by 2, we find that the measure of Q\angle Q is 5555^\circ.

Adım Adım Çözüm

1
Identify the properties of the given triangle.
PQR\triangle PQR is an isosceles triangle with base QRQR and base angles Q=R\angle Q = \angle R.
A triangle with two equal sides is isosceles, and the angles opposite those sides are equal in measure.
2
Apply the triangle angle sum theorem.
P+Q+R=180\angle P + \angle Q + \angle R = 180^\circ
The sum of the measures of the interior angles of any triangle is always 180180^\circ.
3
Substitute the known values and solve for Q\angle Q.
70+2(Q)=180    2(Q)=110    Q=5570^\circ + 2(\angle Q) = 180^\circ \implies 2(\angle Q) = 110^\circ \implies \angle Q = 55^\circ
Substituting P=70\angle P = 70^\circ and R=Q\angle R = \angle Q allows us to solve the linear equation for the unknown angle measure.

Anahtar Kavram

Isosceles Triangle Properties and Triangle Angle Sum Theorem
Tahmini Süre:45s
Soru 2187Soru

For the functions f(x)=4x17f(x) = |4x - 17| and g(x)=32xg(x) = 3 - 2x, what is the value of f(g(5))f(g(5))?

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Cevap: 45

Cevap

The correct answer is 45.
Evaluating the inner function first yields g(5)=32(5)=7g(5) = 3 - 2(5) = -7. Substituting this result into the outer function gives f(7)=4(7)17=45=45f(-7) = |4(-7) - 17| = |-45| = 45.

Adım Adım Çözüm

1
Evaluate the inner function g(5)g(5)
g(5)=32(5)=7g(5) = 3 - 2(5) = -7
In a composite function of the form f(g(x))f(g(x)), the inner function g(x)g(x) must be evaluated first at the given input.
2
Evaluate the outer function f(x)f(x) at the output of the inner function
f(7)=4(7)17=2817=45=45f(-7) = |4(-7) - 17| = |-28 - 17| = |-45| = 45
The output of the inner function, 7-7, becomes the input for the outer function f(x)f(x).

Anahtar Kavram

Function Evaluation and Composition
Soru 2188Soru

In the standard (x,y)(x,y) coordinate plane, the point A(4,3)A(-4, 3) is reflected across the xx-axis and then translated 55 units to the right to map onto point AA'. What are the coordinates of AA'?

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Cevap: (1,3)(1, -3)

Cevap

(1,3)(1, -3)
Reflecting the point A(4,3)A(-4, 3) across the xx-axis negates its yy-coordinate, resulting in (4,3)(-4, -3). Then, translating this point 55 units to the right increases its xx-coordinate by 55, which yields (4+5,3)=(1,3)(-4 + 5, -3) = (1, -3).

Adım Adım Çözüm

1
Reflect the point A(4,3)A(-4, 3) across the xx-axis.
The rule for reflection across the xx-axis is (x,y)(x,y)(x, y) \rightarrow (x, -y). Applying this rule to A(4,3)A(-4, 3) yields the intermediate point (4,3)(-4, -3).
A reflection across the xx-axis negates the yy-coordinate of the point while keeping the xx-coordinate the same.
2
Translate the reflected point (4,3)(-4, -3) by 55 units to the right.
The rule for translating a point hh units to the right is (x,y)(x+h,y)(x, y) \rightarrow (x + h, y). Adding 55 to the xx-coordinate yields (4+5,3)=(1,3)(-4 + 5, -3) = (1, -3).
Translating a point to the right increases its xx-coordinate by the translation distance.

Anahtar Kavram

Applying a sequence of coordinate transformations (reflection followed by translation) to a point.
Tahmini Süre:45s
Soru 2189Soru

A company's net profit is calculated by subtracting its monthly operating costs from its monthly revenue. In a certain month, the company's revenue is 260,000260,000 dollars minus twice its monthly operating costs. If the company wants its monthly net profit to be at least 110,000110,000 dollars, which of the following inequalities represents all possible values of its monthly operating costs, CC, in dollars?

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Cevap: C50,000C \le 50,000

Cevap

The inequality C50,000C \le 50,000
The correct inequality is obtained by setting up the net profit as the revenue (260,0002C260,000 - 2C) minus the operating costs (CC), which simplifies to 260,0003C260,000 - 3C. Setting this profit to be at least 110,000110,000 gives the inequality 260,0003C110,000260,000 - 3C \ge 110,000. Subtracting 260,000260,000 from both sides results in 3C150,000-3C \ge -150,000. Finally, dividing both sides by 3-3 and reversing the inequality sign because of the division by a negative number yields C50,000C \le 50,000.

Adım Adım Çözüm

1
Define the expression for net profit by subtracting the operating costs, CC, from the revenue, which is 260,0002C260,000 - 2C.
Net profit = (260,0002C)C=260,0003C(260,000 - 2C) - C = 260,000 - 3C
Net profit is defined as revenue minus operating costs.
2
Set up the inequality where the net profit is at least 110,000110,000.
260,0003C110,000260,000 - 3C \ge 110,000
The phrase 'at least' translates to the 'greater than or equal to' inequality sign (\ge).
3
Subtract 260,000260,000 from both sides of the inequality.
3C150,000-3C \ge -150,000
Isolate the term containing the variable CC.
4
Divide both sides by 3-3 and reverse the inequality sign.
C50,000C \le 50,000
Dividing an inequality by a negative number requires reversing the direction of the inequality sign.

Anahtar Kavram

Translating and Solving Algebraic Word Problems
Tahmini Süre:1m 30s
Soru 2190Soru

For the functions f(x)=(x2)25f(x) = (x - 2)^2 - 5 and g(x)=x+13g(x) = |x + 1| - 3, what is the value of f(g(2))f(g(-2))?

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Cevap: 11

Cevap

11
To find the value of f(g(2))f(g(-2)), first evaluate the inner function g(x)g(x) at x=2x = -2. Substituting 2-2 into g(x)=x+13g(x) = |x + 1| - 3 gives g(2)=2+13=13=2g(-2) = |-2 + 1| - 3 = 1 - 3 = -2. Next, substitute this output as the input for the outer function f(x)f(x). Substituting 2-2 into f(x)=(x2)25f(x) = (x - 2)^2 - 5 yields f(2)=(22)25=(4)25=165=11f(-2) = (-2 - 2)^2 - 5 = (-4)^2 - 5 = 16 - 5 = 11.

Adım Adım Çözüm

1
Evaluate the inner function at the given input value
g(2)=2+13=13=13=2g(-2) = |-2 + 1| - 3 = |-1| - 3 = 1 - 3 = -2
In function composition f(g(x))f(g(x)), the inner function must be evaluated first to determine the input for the outer function.
2
Evaluate the outer function using the output of the inner function
f(2)=(22)25=(4)25=165=11f(-2) = (-2 - 2)^2 - 5 = (-4)^2 - 5 = 16 - 5 = 11
Substitute the result from the inner function evaluation into the outer function to find the final value.

Anahtar Kavram

Function composition and evaluation
Tahmini Süre:1m 0s
Soru 2191Soru

A system administrator monitors the temperatures of two servers, Server A and Server B, over a period of tt hours after midnight. The temperature of Server A, in degrees Celsius, is modeled by a linear function of time. At t=2t = 2 hours, the temperature is 30C30^\circ\text{C}, and at t=at = a hours (where a>2a > 2), the temperature is (30+a22a)C(30 + a^2 - 2a)^\circ\text{C}. The temperature of Server B, in degrees Celsius, is also modeled by a linear function of time. At t=1t = 1 hour, Server B's temperature is 25C25^\circ\text{C}, and at t=at = a hours, its temperature is (a2+30)C(a^2 + 30)^\circ\text{C}. If the temperature of Server B increases at a constant rate that is 1.51.5 times the constant rate of temperature increase of Server A, what is the value of aa?

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Cevap: 5

Cevap

The value of aa is 5.
To find the rate of change (slope) for each server, we apply the slope formula m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1}. For Server A, the slope is mA=(30+a22a)30a2=am_A = \frac{(30 + a^2 - 2a) - 30}{a - 2} = a. For Server B, the slope is mB=(a2+30)25a1=a2+5a1m_B = \frac{(a^2 + 30) - 25}{a - 1} = \frac{a^2 + 5}{a - 1}. We are given that mB=1.5mAm_B = 1.5 m_A, which yields the equation a2+5a1=1.5a\frac{a^2 + 5}{a - 1} = 1.5a. Multiplying both sides by a1a - 1 gives a2+5=1.5a(a1)=1.5a21.5aa^2 + 5 = 1.5a(a - 1) = 1.5a^2 - 1.5a. Grouping all terms on one side gives 0.5a21.5a5=00.5a^2 - 1.5a - 5 = 0. Multiplying the equation by 2 results in a23a10=0a^2 - 3a - 10 = 0, which factors as (a5)(a+2)=0(a - 5)(a + 2) = 0. Since a>2a > 2, the only valid solution is the positive root, which is 5.

Adım Adım Çözüm

1
Calculate the constant rate of temperature increase (slope) for Server A, mAm_A, using the coordinates (2,30)(2, 30) and (a,30+a22a)(a, 30 + a^2 - 2a).
mA=(30+a22a)30a2=a22aa2=a(a2)a2=am_A = \frac{(30 + a^2 - 2a) - 30}{a - 2} = \frac{a^2 - 2a}{a - 2} = \frac{a(a-2)}{a-2} = a (since a>2a > 2)
The constant rate of change of a linear temperature model is represented by the slope of the line passing through its data points.
2
Calculate the constant rate of temperature increase (slope) for Server B, mBm_B, using the coordinates (1,25)(1, 25) and (a,a2+30)(a, a^2 + 30).
mB=(a2+30)25a1=a2+5a1m_B = \frac{(a^2 + 30) - 25}{a - 1} = \frac{a^2 + 5}{a - 1}
The constant rate of change of Server B is represented by the slope of the line passing through its data points.
3
Set up the equation using the given relationship that Server B's rate of increase is 1.51.5 times Server A's rate (mB=1.5mAm_B = 1.5 m_A).
1.5a=a2+5a11.5a = \frac{a^2 + 5}{a - 1}
Equating the rate of change of Server B to 1.5 times the rate of change of Server A allows us to write an equation in terms of the variable aa.
4
Solve the equation for aa by cross-multiplying and simplifying the resulting quadratic equation.
1.5a(a1)=a2+5    1.5a21.5a=a2+5    0.5a21.5a5=0    a23a10=0    (a5)(a+2)=01.5a(a - 1) = a^2 + 5 \implies 1.5a^2 - 1.5a = a^2 + 5 \implies 0.5a^2 - 1.5a - 5 = 0 \implies a^2 - 3a - 10 = 0 \implies (a-5)(a+2) = 0
Cross-multiplying eliminates the fraction, and grouping all terms on one side forms a standard quadratic equation that can be factored.
5
Identify the valid value of aa that satisfies the initial domain constraint.
a=5a = 5 (since a=2a = -2 is rejected because the problem states a>2a > 2)
The solution must satisfy the given condition that a>2a > 2 for the time intervals to be valid.

Anahtar Kavram

Calculating and equating rates of change (slopes) of linear functions using the slope formula m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1} and solving the resulting quadratic equation.
Soru 2192Soru

On a coordinate map, two tracking stations are located at the points (2,3)(2, -3) and (6,12)(-6, 12). What is the straight-line distance, in map units, between the two stations?

Cevabı ve açıklamayı göster

Cevap: 17

Cevap

The straight-line distance between the two stations is 17 map units.
Applying the coordinate distance formula to the coordinates (2,3)(2, -3) and (6,12)(-6, 12) yields a distance of (62)2+(12(3))2=(8)2+152=64+225=289=17\sqrt{(-6 - 2)^2 + (12 - (-3))^2} = \sqrt{(-8)^2 + 15^2} = \sqrt{64 + 225} = \sqrt{289} = 17.

Adım Adım Çözüm

1
Identify coordinates of the two stations.
(x1,y1)=(2,3)(x_1, y_1) = (2, -3) and (x2,y2)=(6,12)(x_2, y_2) = (-6, 12)
Defining the coordinate variables is necessary to apply the formula correctly.
2
Apply the distance formula.
d=(62)2+(12(3))2d = \sqrt{(-6 - 2)^2 + (12 - (-3))^2}
The distance formula calculates the straight-line distance between two coordinates.
3
Simplify the arithmetic terms.
d=(8)2+152=64+225=289d = \sqrt{(-8)^2 + 15^2} = \sqrt{64 + 225} = \sqrt{289}
Simplify the differences and squares under the radical.
4
Calculate the final square root.
d=17d = 17
The square root of 289 is 17.

Anahtar Kavram

Distance Formula
Soru 2193Soru

A circle is graphed in the standard (x,y)(x, y) coordinate plane such that it is tangent to the xx-axis at (4,0)(4, 0) and tangent to the yy-axis at (0,4)(0, 4). A line segment has one of its endpoints at the center of this circle and its midpoint at the point (1,1)(1, -1). What is the total length of this line segment?

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Cevap: 2342\sqrt{34}

Cevap

The total length of the line segment is 2342\sqrt{34}.
The center of the circle is determined to be C(4,4)C(4, 4) based on the points of tangency at (4,0)(4, 0) and (0,4)(0, 4). The distance between the center C(4,4)C(4, 4) and the midpoint M(1,1)M(1, -1) is calculated using the distance formula to be 34\sqrt{34}. Since the midpoint divides the segment into two equal halves, the total length of the segment is twice this distance, which is 2342\sqrt{34}.

Adım Adım Çözüm

1
Determine the coordinates of the center of the circle.
The center of the circle is C(4,4)C(4, 4).
Since the circle is tangent to the xx-axis at (4,0)(4, 0), its center must lie on the vertical line x=4x = 4. Since it is tangent to the yy-axis at (0,4)(0, 4), its center must lie on the horizontal line y=4y = 4. Their intersection gives the center of the circle at C(4,4)C(4, 4).
2
Calculate the distance from the center of the circle to the midpoint of the segment.
The distance is 34\sqrt{34}.
Using the distance formula between the center C(4,4)C(4, 4) and the midpoint M(1,1)M(1, -1): d(C,M)=(14)2+(14)2=(3)2+(5)2=9+25=34d(C, M) = \sqrt{(1 - 4)^2 + (-1 - 4)^2} = \sqrt{(-3)^2 + (-5)^2} = \sqrt{9 + 25} = \sqrt{34}.
3
Find the total length of the line segment.
The total length is 2342\sqrt{34}.
Since the midpoint divides the segment into two equal parts, the total length is twice the distance from one endpoint to the midpoint: Length=2×d(C,M)=234\text{Length} = 2 \times d(C, M) = 2\sqrt{34}.

Anahtar Kavram

Using circle tangencies to find the center, and applying the distance and midpoint formulas to determine segment properties.
Tahmini Süre:1m 30s
Soru 2194Soru

In the standard (x,y)(x, y) coordinate plane, if the slope of a line passing through the points (k,k2)(k, k^2) and (k+1,(k+1)2)(k+1, (k+1)^2) is an integer, then kk must be an integer. Is this statement true or false?

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Cevap: False

Cevap

False
The statement is false because the simplified slope of the line is 2k+12k + 1. The slope 2k+12k + 1 is an integer for any half-integer value of kk (such as k=0.5k = 0.5, which yields a slope of 22), showing that kk does not have to be an integer.

Adım Adım Çözüm

1
Use the slope formula m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1} with the given coordinates (k,k2)(k, k^2) and (k+1,(k+1)2)(k+1, (k+1)^2).
The slope is m=(k+1)2k2(k+1)km = \frac{(k+1)^2 - k^2}{(k+1) - k}.
To express the slope of the line in terms of the variable kk.
2
Simplify the numerator and denominator of the slope expression.
m=k2+2k+1k21=2k+1m = \frac{k^2 + 2k + 1 - k^2}{1} = 2k + 1.
To obtain a simplified algebraic expression for the slope.
3
Set the slope equal to an arbitrary integer nn and solve for kk.
2k+1=n    k=n122k + 1 = n \implies k = \frac{n-1}{2}.
To find the set of values for kk that yield an integer slope.
4
Evaluate if kk must be an integer by choosing an integer value for nn.
If n=2n = 2, then k=212=0.5k = \frac{2-1}{2} = 0.5, which is not an integer.
To test the truth value of the statement by finding a counterexample.

Anahtar Kavram

Determining the slope of a line from two coordinate points and analyzing the algebraic properties of the slope expression.
Soru 2195Soru

A hyperbola is defined by the equation 9x24y236x8y4=09x^2 - 4y^2 - 36x - 8y - 4 = 0 in the standard (x,y)(x, y) coordinate plane. What is the slope of the asymptote of this hyperbola that has a positive slope?

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Cevap: 1.5

Cevap

The positive slope of the asymptotes is 1.5.
By converting the general form of the hyperbola equation into standard form, we determine that it is a horizontal hyperbola with a=2a = 2 and b=3b = 3. The slopes of the asymptotes for a horizontal hyperbola are ±ba\pm \frac{b}{a}, making the positive slope equal to 32=1.5\frac{3}{2} = 1.5.

Adım Adım Çözüm

1
Group x-terms and y-terms, and move the constant to the other side.
9(x24x)4(y2+2y)=49(x^2 - 4x) - 4(y^2 + 2y) = 4
This prepares the equation for completing the square.
2
Complete the square for the quadratic expressions in x and y.
9(x2)24(y+1)2=369(x - 2)^2 - 4(y + 1)^2 = 36
Completing the square yields 9[(x2)24]4[(y+1)21]=4    9(x2)2364(y+1)2+4=49[(x-2)^2 - 4] - 4[(y+1)^2 - 1] = 4 \implies 9(x-2)^2 - 36 - 4(y+1)^2 + 4 = 4.
3
Divide both sides by 36 to format the equation in standard hyperbola form.
(x2)24(y+1)29=1\frac{(x-2)^2}{4} - \frac{(y+1)^2}{9} = 1
The standard form of a horizontal hyperbola centered at (h,k)(h, k) is (xh)2a2(yk)2b2=1\frac{(x-h)^2}{a^2} - \frac{(y-k)^2}{b^2} = 1.
4
Identify the values of a and b from the denominators.
a=2a = 2 and b=3b = 3
Since a2=4a^2 = 4 and b2=9b^2 = 9, taking the square roots gives a=2a = 2 and b=3b = 3.
5
Determine the positive slope of the asymptotes using the formula for a horizontal hyperbola.
m=ba=1.5m = \frac{b}{a} = 1.5
The asymptotes for a horizontal hyperbola are given by yk=±ba(xh)y - k = \pm \frac{b}{a}(x - h), so the positive slope is ba=32=1.5\frac{b}{a} = \frac{3}{2} = 1.5.

Anahtar Kavram

Rewriting a hyperbola equation from general form to standard form to find asymptote equations.
Tahmini Süre:1m 30s
Soru 2196Soru

In quadrilateral ABCDABCD, diagonal ACAC divides the figure into two triangles, ABC\triangle ABC and ACD\triangle ACD. The lengths of three of the sides are AB=6 cmAB = 6\text{ cm}, BC=8 cmBC = 8\text{ cm}, and CD=12 cmCD = 12\text{ cm}. If the length of side ADAD is an integer k cmk\text{ cm}, what is the sum of the minimum and maximum possible values of kk?

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Cevap: 26

Cevap

26
To find the minimum and maximum values of the integer side kk, we first determine the range of the shared diagonal ACAC. In the bottom triangle, the Triangle Inequality Theorem requires 2<AC<142 < AC < 14. In the top triangle, the theorem requires 12AC<k<12+AC|12 - AC| < k < 12 + AC. To minimize kk, we look at the lower bound 12AC|12 - AC|. Since ACAC can be 1212, the lower bound can be 00, meaning k>0k > 0, so the minimum integer value is 11. To maximize kk, we look at the upper bound 12+AC12 + AC. Since AC<14AC < 14, the upper bound is k<26k < 26, so the maximum integer value is 2525. The sum of these values is 1+25=261 + 25 = 26.

Adım Adım Çözüm

1
Find the possible range of lengths for the diagonal ACAC using ABC\triangle ABC.
2 cm<AC<14 cm2\text{ cm} < AC < 14\text{ cm}
According to the Triangle Inequality Theorem, the length of side ACAC must be greater than BCAB=86=2 cm|BC - AB| = 8 - 6 = 2\text{ cm} and less than BC+AB=8+6=14 cmBC + AB = 8 + 6 = 14\text{ cm}.
2
Set up the inequality for side AD=kAD = k in ACD\triangle ACD.
12AC<k<12+AC|12 - AC| < k < 12 + AC
By the Triangle Inequality Theorem applied to ACD\triangle ACD, the length kk must be greater than the absolute difference CDAC|CD - AC| and less than the sum CD+ACCD + AC.
3
Find the minimum possible integer value for kk.
k=1k = 1
Since ACAC can be any real number between 22 and 1414, we can choose AC=12AC = 12, which makes the lower bound 1212=0|12 - 12| = 0. Thus, we have k>0k > 0. The smallest integer greater than 00 is 11. We verify that k=1k = 1 is possible by choosing AC=12AC = 12, which satisfies the inequalities for both triangles.
4
Find the maximum possible integer value for kk.
k=25k = 25
Since AC<14AC < 14, the upper bound is k<12+AC<12+14=26k < 12 + AC < 12 + 14 = 26. Thus, we have k<26k < 26. The largest integer less than 2626 is 2525. We verify that k=25k = 25 is possible by choosing AC=13.5AC = 13.5, which satisfies the inequalities for both triangles.
5
Calculate the sum of the minimum and maximum possible integer values of kk.
1+25=261 + 25 = 26
To find the sum of the minimum and maximum values of kk as requested by the question.

Anahtar Kavram

The Triangle Inequality Theorem states that for any triangle, the sum of the lengths of any two sides must be strictly greater than the length of the remaining side.
Soru 2197Soru

In the standard (x,y)(x, y) coordinate plane, a line segment ABAB has endpoints A(2,5)A(2, 5) and B(6,1)B(6, -1). Segment ABAB is reflected across the line y=xy = -x to form segment ABA'B'. Then, segment ABA'B' is dilated by a scale factor of 33 with a center of dilation at C(2,1)C(2, -1) to form segment ABA''B''. What is the sum of the xx- and yy-coordinates of the midpoint of segment ABA''B''?

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Cevap: -20

Cevap

-20
To find the coordinates of the midpoint of the transformed segment ABA''B'', we can track the midpoint of the original segment ABAB through each transformation. The midpoint of ABAB is M(4,2)M(4, 2). Reflecting MM across the line y=xy = -x swaps and negates its coordinates, resulting in M(2,4)M'(-2, -4). Dilating MM' by a scale factor of 33 centered at C(2,1)C(2, -1) means finding the point MM'' such that the vector CM\vec{CM''} is 33 times the vector CM\vec{CM'}. This is computed as M=(2+3(22),1+3(4(1)))=(10,10)M'' = (2 + 3(-2 - 2), -1 + 3(-4 - (-1))) = (-10, -10). The sum of these coordinates is 10+(10)=20-10 + (-10) = -20.

Adım Adım Çözüm

1
Find the midpoint of the original segment ABAB.
The midpoint MM of segment ABAB is M=(2+62,5+(1)2)=(4,2)M = \left(\frac{2 + 6}{2}, \frac{5 + (-1)}{2}\right) = (4, 2).
Since rigid transformations (reflections) and similarity transformations (dilations) preserve midpoints, we can find the final midpoint by applying the sequence of transformations directly to the initial midpoint.
2
Reflect the midpoint M(4,2)M(4, 2) across the line y=xy = -x to find the midpoint MM' of segment ABA'B'.
Applying the reflection rule (x,y)(y,x)(x, y) \rightarrow (-y, -x) to M(4,2)M(4, 2) yields M(2,4)M'(-2, -4).
Reflecting a point across the line y=xy = -x swaps its coordinates and negates both values.
3
Dilate the midpoint M(2,4)M'(-2, -4) by a scale factor of 33 with the center of dilation at C(2,1)C(2, -1) to find the midpoint MM'' of segment ABA''B''.
Using the dilation formula (x,y)=(xc+k(xxc),yc+k(yyc))(x'', y'') = (x_c + k(x' - x_c), y_c + k(y' - y_c)) with C(2,1)C(2, -1) and k=3k = 3: x=2+3(22)=10x'' = 2 + 3(-2 - 2) = -10, and y=1+3(4(1))=10y'' = -1 + 3(-4 - (-1)) = -10. This gives the midpoint M(10,10)M''(-10, -10).
A dilation centered at (xc,yc)(x_c, y_c) scales the horizontal and vertical distances from the center to the point by the scale factor kk.
4
Calculate the sum of the xx- and yy-coordinates of MM.
The sum of the coordinates is 10+(10)=20-10 + (-10) = -20.
The question asks for the sum of the coordinates of the final midpoint.

Anahtar Kavram

Applying composite transformations in the coordinate plane to geometric figures and midpoints.
Soru 2198Soru

In the standard (x,y)(x, y) coordinate plane, line segment ABAB has endpoints A(2,4)A(-2, 4) and B(4,2)B(4, 2). The segment is rotated 9090^\circ counterclockwise about the origin, then reflected across the line y=xy = -x, and finally translated 33 units to the right and 22 units down. What are the coordinates of the midpoint of the final image of the segment?

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Cevap: (2,1)(2, 1)

Cevap

(2,1)(2, 1)
The correct midpoint is (2,1)(2, 1). First, the midpoint of the original segment ABAB is calculated using the midpoint formula, yielding (1,3)(1, 3). Rotating this point 9090^\circ counterclockwise about the origin maps (x,y)(x, y) to (y,x)(-y, x), which gives (3,1)(-3, 1). Reflecting (3,1)(-3, 1) across the line y=xy = -x maps (x,y)(x, y) to (y,x)(-y, -x), resulting in (1,3)(-1, 3). Finally, translating this point 33 units to the right and 22 units down yields (1+3,32)=(2,1)(-1 + 3, 3 - 2) = (2, 1).

Adım Adım Çözüm

1
Find the midpoint of the original line segment ABAB.
M(1,3)M(1, 3)
The midpoint formula is M=(x1+x22,y1+y22)M = \left(\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2}\right). Substituting the coordinates of A(2,4)A(-2, 4) and B(4,2)B(4, 2) yields (2+42,4+22)=(1,3)\left(\frac{-2 + 4}{2}, \frac{4 + 2}{2}\right) = (1, 3).
2
Apply a 9090^\circ counterclockwise rotation about the origin to the midpoint.
M(3,1)M'(-3, 1)
A 9090^\circ counterclockwise rotation about the origin maps (x,y)(y,x)(x, y) \rightarrow (-y, x). Applying this rule to M(1,3)M(1, 3) gives (3,1)(-3, 1).
3
Reflect the rotated point across the line y=xy = -x.
M(1,3)M''(-1, 3)
A reflection across the line y=xy = -x maps (x,y)(y,x)(x, y) \rightarrow (-y, -x). Applying this rule to M(3,1)M'(-3, 1) gives (1,3)(-1, 3).
4
Translate the reflected point 33 units right and 22 units down.
M(2,1)M'''(2, 1)
A translation of 33 units right and 22 units down maps (x,y)(x+3,y2)(x, y) \rightarrow (x + 3, y - 2). Translating M(1,3)M''(-1, 3) yields (1+3,32)=(2,1)(-1 + 3, 3 - 2) = (2, 1).

Anahtar Kavram

Composite transformations of geometric figures in the coordinate plane

Alternatif Yöntem

Instead of transforming the midpoint, you can transform the individual endpoints A(2,4)A(-2, 4) and B(4,2)B(4, 2) through all three steps. Point A(2,4)A(-2, 4) becomes A(4,2)A(2,4)A(5,2)A'(-4, -2) \rightarrow A''(2, 4) \rightarrow A'''(5, 2). Point B(4,2)B(4, 2) becomes B(2,4)B(4,2)B(1,0)B'(-2, 4) \rightarrow B''(-4, 2) \rightarrow B'''(-1, 0). The midpoint of AA''' and BB''' is then calculated to be (5+(1)2,2+02)=(2,1)\left(\frac{5 + (-1)}{2}, \frac{2 + 0}{2}\right) = (2, 1).
Tahmini Süre:1m 30s
Soru 2199Soru

In the standard (x,y)(x,y) coordinate plane, line qq is perpendicular to the line with equation y=34x2y = \frac{3}{4}x - 2. If line qq passes through the point (2,1)(2, 1), what is the yy-intercept of line qq?

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Cevap: 113\frac{11}{3}

Cevap

The yy-intercept of line qq is 113\frac{11}{3}.
The slope of the given line y=34x2y = \frac{3}{4}x - 2 is 34\frac{3}{4}. The slope of a perpendicular line is the negative reciprocal of the original slope, which is 43-\frac{4}{3}. Using the point-slope form of a linear equation with the point (2,1)(2, 1) gives y1=43(x2)y - 1 = -\frac{4}{3}(x - 2). To find the yy-intercept, set x=0x = 0, which gives y1=43(2)=83y - 1 = -\frac{4}{3}(-2) = \frac{8}{3}. Adding 11 to both sides yields y=83+1=113y = \frac{8}{3} + 1 = \frac{11}{3}. Therefore, the correct yy-intercept is 113\frac{11}{3}.

Adım Adım Çözüm

1
Determine the slope of the perpendicular line qq.
The slope of the given line is 34\frac{3}{4}, so the slope of line qq (the negative reciprocal) is 43-\frac{4}{3}.
Perpendicular lines have slopes that are negative reciprocals of each other.
2
Write the equation of line qq using the point-slope form with the point (2,1)(2, 1).
y1=43(x2)y - 1 = -\frac{4}{3}(x - 2)
The point-slope form yy1=m(xx1)y - y_1 = m(x - x_1) is used to find the equation of a line given its slope and a point on the line.
3
Find the yy-intercept by setting x=0x = 0 and solving for yy.
y1=43(02)y1=83y=83+1=113y - 1 = -\frac{4}{3}(0 - 2) \Rightarrow y - 1 = \frac{8}{3} \Rightarrow y = \frac{8}{3} + 1 = \frac{11}{3}
The yy-intercept of a line is the value of yy when x=0x = 0.

Anahtar Kavram

The slope of a line perpendicular to a line with slope mm is 1m-\frac{1}{m}. The equation of a line can be written in point-slope form as yy1=m(xx1)y - y_1 = m(x - x_1).
Soru 2200Soru

If xx is a real number greater than 2 such that log2(x24)log2(x2)=3\log_2(x^2 - 4) - \log_2(x - 2) = 3, what is the value of xx?

Cevabı ve açıklamayı göster

Cevap: 6

Cevap

The value of xx is 6.
Applying the quotient property of logarithms simplifies the equation to log2(x24x2)=3\log_2\left(\frac{x^2 - 4}{x - 2}\right) = 3. Factoring the numerator as (x2)(x+2)(x-2)(x+2) and canceling the common factor (x2)(x-2) yields log2(x+2)=3\log_2(x+2) = 3. Rewriting this in exponential form gives x+2=23=8x + 2 = 2^3 = 8, which yields x=6x = 6.

Adım Adım Çözüm

1
Combine the logarithmic terms on the left side of the equation using the quotient property of logarithms: logbAlogbB=logb(AB)\log_b A - \log_b B = \log_b\left(\frac{A}{B}\right).
log2(x24x2)=3\log_2\left(\frac{x^2 - 4}{x - 2}\right) = 3
Consolidating the two logarithmic terms simplifies the equation into a single logarithmic term.
2
Factor the numerator as a difference of squares and simplify the rational expression.
log2(x+2)=3\log_2(x + 2) = 3 (since x>2x > 2, x20x - 2 \neq 0)
Factoring x24x^2 - 4 as (x2)(x+2)(x - 2)(x + 2) allows the cancellation of the common factor (x2)(x - 2).
3
Convert the logarithmic equation into its equivalent exponential form: logbY=cY=bc\log_b Y = c \Rightarrow Y = b^c.
x+2=23x + 2 = 2^3
This removes the logarithm and sets up a linear equation to solve.
4
Evaluate the exponent and solve for xx.
x+2=8x=6x + 2 = 8 \Rightarrow x = 6
Evaluating 232^3 as 8 and subtracting 2 from both sides isolates xx.

Anahtar Kavram

Solving logarithmic equations using properties of logarithms and algebraic factoring
Tahmini Süre:1m 30s
ÖncekiSayfa 110 / 278Sonraki
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