Tüm alıştırma soruları

5556 soru

Soru 2441Soru

The circle defined by the equation x2+y26x+8y11=0x^2 + y^2 - 6x + 8y - 11 = 0 is plotted in the standard (x,y)(x, y) coordinate plane. A second circle has a center that is the reflection of the first circle's center across the line y=xy = x. If the radius of the second circle is twice the radius of the first circle, which of the following is the equation of the second circle?

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Cevap: (x+4)2+(y3)2=144(x + 4)^2 + (y - 3)^2 = 144

Cevap

(x+4)2+(y3)2=144(x + 4)^2 + (y - 3)^2 = 144
Completing the square on x2+y26x+8y11=0x^2 + y^2 - 6x + 8y - 11 = 0 gives (x3)2+(y+4)2=36(x - 3)^2 + (y + 4)^2 = 36. The center is (3,4)(3, -4) and the radius is 66. Reflecting (3,4)(3, -4) across the line y=xy = x swaps the coordinates, yielding the new center (4,3)(-4, 3). Doubling the radius yields 1212. The equation of the second circle is therefore (x(4))2+(y3)2=122(x - (-4))^2 + (y - 3)^2 = 12^2, which simplifies to (x+4)2+(y3)2=144(x + 4)^2 + (y - 3)^2 = 144.

Adım Adım Çözüm

1
Group the xx and yy terms of the given equation x2+y26x+8y11=0x^2 + y^2 - 6x + 8y - 11 = 0 and add 11 to both sides.
(x26x)+(y2+8y)=11(x^2 - 6x) + (y^2 + 8y) = 11
To prepare the terms for completing the square.
2
Complete the square for both the xx and yy groups by adding (6/2)2=9(6/2)^2 = 9 and (8/2)2=16(8/2)^2 = 16 to both sides.
(x3)2+(y+4)2=36(x - 3)^2 + (y + 4)^2 = 36
To express the circle's equation in standard form (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2.
3
Identify the center and radius of the first circle from the standard form.
Center is (3,4)(3, -4) and radius is r1=36=6r_1 = \sqrt{36} = 6.
These characteristics are needed to find the properties of the second circle.
4
Reflect the center (3,4)(3, -4) across the line y=xy = x by swapping the xx and yy coordinates, and double the radius.
New center is (4,3)(-4, 3) and new radius is r2=2×6=12r_2 = 2 \times 6 = 12.
To satisfy the geometric transformations specified in the problem statement.
5
Write the standard equation of the second circle using the new center (4,3)(-4, 3) and new radius 1212.
(x+4)2+(y3)2=144(x + 4)^2 + (y - 3)^2 = 144
Substituting h=4h = -4, k=3k = 3, and r=12r = 12 into the standard equation (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2.

Anahtar Kavram

Completing the square to find standard circle characteristics, and applying reflections across the line y=xy = x.
Tahmini Süre:2m 0s
Soru 2442Soru

In the standard (x,y)(x,y) coordinate plane, a line segment OQOQ connects the origin O(0,0)O(0,0) to a point QQ in the first quadrant. The segment OQOQ has a length of 1010 units and makes an angle of 6060^\circ with the positive xx-axis. An isosceles right triangle OQR\triangle OQR is constructed such that the right angle is at QQ, the leg QRQR has a length of 1010 units, and point RR lies in the first quadrant. What are the coordinates of point RR?

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Cevap: (5+53,535)(5 + 5\sqrt{3}, 5\sqrt{3} - 5)

Cevap

The coordinates (5+53,535)(5 + 5\sqrt{3}, 5\sqrt{3} - 5)
The correct answer is (5+53,535)(5 + 5\sqrt{3}, 5\sqrt{3} - 5) because constructing two helper 30-60-9030^\circ\text{-}60^\circ\text{-}90^\circ right triangles allows us to determine both the coordinates of QQ as (5,53)(5, 5\sqrt{3}) and the horizontal and vertical shifts to RR as +53+5\sqrt{3} and 5-5 respectively.

Adım Adım Çözüm

1
Project point QQ onto the xx-axis to form a 30-60-9030^\circ\text{-}60^\circ\text{-}90^\circ right triangle.
The horizontal leg is 10cos(60)=510 \cos(60^\circ) = 5 and the vertical leg is 10sin(60)=5310 \sin(60^\circ) = 5\sqrt{3}.
The hypotenuse OQOQ has a length of 1010 and makes a 6060^\circ angle with the positive xx-axis.
2
Determine the coordinates of point QQ.
Q=(5,53)Q = (5, 5\sqrt{3}).
Point QQ is in the first quadrant, so both coordinates are positive.
3
Determine the orientation of segment QRQR.
Segment QRQR must make a 3030^\circ angle below the horizontal line passing through QQ (going down and to the right).
Since OQR\triangle OQR is a right isosceles triangle with the right angle at QQ, QRQR is perpendicular to OQOQ and has length 1010. To keep RR in the first quadrant, QRQR must rotate clockwise from OQOQ by 9090^\circ.
4
Construct a helper 30-60-9030^\circ\text{-}60^\circ\text{-}90^\circ right triangle under QRQR to find the changes in xx and yy.
The horizontal change is +10cos(30)=+53+10 \cos(30^\circ) = +5\sqrt{3} and the vertical change is 10sin(30)=5-10 \sin(30^\circ) = -5.
The hypotenuse of this triangle is QR=10QR = 10, and the angle with the horizontal is 3030^\circ.
5
Calculate the coordinates of RR by applying the changes to the coordinates of QQ.
R=(5+53,535)R = (5 + 5\sqrt{3}, 5\sqrt{3} - 5).
Add the horizontal change to xQx_Q and the vertical change to yQy_Q.

Anahtar Kavram

Solving coordinate geometry problems using 30-60-9030^\circ\text{-}60^\circ\text{-}90^\circ special right triangles.
Soru 2443Soru

A regular octagon has 8 congruent interior angles. What is the degree measure of one of these interior angles?

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Cevap: 135

Cevap

The degree measure of one interior angle of a regular octagon is 135 degrees.
The interior angles of a regular octagon sum to 10801080^\circ because (82)×180=1080(8-2) \times 180^\circ = 1080^\circ. Since a regular octagon has 8 equal angles, dividing 10801080^\circ by 88 results in 135135^\circ per interior angle.

Adım Adım Çözüm

1
Identify the number of sides in a regular octagon.
The number of sides, nn, is 88.
An octagon is defined as a polygon with 8 sides and 8 angles.
2
Calculate the sum of the interior angles of the octagon.
The sum of the interior angles is 10801080^\circ.
The sum of the interior angles of any convex polygon with nn sides is (n2)×180(n-2) \times 180^\circ. For n=8n = 8, this is (82)×180=6×180=1080(8 - 2) \times 180^\circ = 6 \times 180^\circ = 1080^\circ.
3
Find the measure of one interior angle by dividing the sum by the number of angles.
Each interior angle measures 135135^\circ.
A regular polygon has congruent interior angles. Therefore, dividing the total sum of 10801080^\circ by the 88 congruent angles yields the measure of each individual interior angle: 1080÷8=1351080^\circ \div 8 = 135^\circ.

Anahtar Kavram

The sum of the interior angles of an nn-sided convex polygon is (n2)×180(n-2) \times 180^\circ. For a regular polygon, each interior angle has a measure of (n2)×180n\frac{(n-2) \times 180^\circ}{n}.
Soru 2444Soru

In the standard (x,y)(x, y) coordinate plane, where 11 unit represents 11 kilometer, a playground is located at (1,10)(1, 10) and a picnic shelter is located at (5,2)(5, -2). A water fountain is to be placed exactly halfway between the playground and the picnic shelter. What is the distance, in kilometers, from the origin (0,0)(0, 0) to the water fountain?

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Cevap: 5

Cevap

The distance from the origin to the water fountain is 55 kilometers.
The midpoint of the segment representing the water fountain is determined to be (3,4)(3, 4). The distance from the origin (0,0)(0, 0) to (3,4)(3, 4) is found using the Pythagorean relation, yielding 32+42=5\sqrt{3^2 + 4^2} = 5 kilometers.

Adım Adım Çözüm

1
Find the coordinates of the midpoint between (1,10)(1, 10) and (5,2)(5, -2).
The midpoint is (3,4)(3, 4).
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 given endpoints gives M=(1+52,10+(2)2)=(3,4)M = \left(\frac{1 + 5}{2}, \frac{10 + (-2)}{2}\right) = (3, 4).
2
Calculate the distance from the origin (0,0)(0, 0) to the midpoint (3,4)(3, 4).
The distance is 55 kilometers.
The distance formula from the origin to any point (x,y)(x, y) is d=x2+y2d = \sqrt{x^2 + y^2}. Substituting the coordinates (3,4)(3, 4) yields d=32+42=9+16=25=5d = \sqrt{3^2 + 4^2} = \sqrt{9 + 16} = \sqrt{25} = 5.

Anahtar Kavram

Using the midpoint formula to find the center of a line segment, followed by the distance formula from the origin to that point.
Soru 2445Soru

A triangle has side lengths of 77, x+2x+2, and 2x12x-1, where xx is an integer. What is the total number of possible values for xx?

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Cevap: 7

Cevap

The total number of possible integer values for xx is 77.
According to the Triangle Inequality Theorem, a triangle is formed if and only if the sum of any two side lengths is strictly greater than the third side length. Solving the three inequalities 7+(x+2)>2x17 + (x+2) > 2x-1, 7+(2x1)>x+27 + (2x-1) > x+2, and (x+2)+(2x1)>7(x+2) + (2x-1) > 7 gives x<10x < 10, x>4x > -4, and x>2x > 2. The overlapping interval is 2<x<102 < x < 10. The integers in this range are {3,4,5,6,7,8,9}\{3, 4, 5, 6, 7, 8, 9\}, which gives a total of 77 possible integer values.

Adım Adım Çözüm

1
Set up the three inequalities required by the Triangle Inequality Theorem.
1) 7+(x+2)>2x17 + (x+2) > 2x-1
2) 7+(2x1)>x+27 + (2x-1) > x+2
3) (x+2)+(2x1)>7(x+2) + (2x-1) > 7
The Triangle Inequality Theorem states that the sum of the lengths of any two sides of a triangle must be strictly greater than the length of the remaining side.
2
Solve the first inequality: 7+(x+2)>2x17 + (x+2) > 2x-1.
x<10x < 10
Simplifying the left side yields x+9>2x1x + 9 > 2x - 1. Subtracting xx and adding 11 to both sides results in 10>x10 > x, which means x<10x < 10.
3
Solve the second inequality: 7+(2x1)>x+27 + (2x-1) > x+2.
x>4x > -4
Simplifying the left side yields 2x+6>x+22x + 6 > x + 2. Subtracting xx and 66 from both sides results in x>4x > -4.
4
Solve the third inequality: (x+2)+(2x1)>7(x+2) + (2x-1) > 7.
x>2x > 2
Simplifying the left side yields 3x+1>73x + 1 > 7. Subtracting 11 and dividing by 33 results in x>2x > 2.
5
Determine the combined range for xx and identify the valid integers.
The combined range is 2<x<102 < x < 10. The valid integers are 3,4,5,6,7,8,3, 4, 5, 6, 7, 8, and 99.
To satisfy all three inequalities, xx must be greater than 22, greater than 4-4, and less than 1010, which simplifies to 2<x<102 < x < 10.
6
Count the total number of valid integer values for xx.
There are 77 integer values.
Counting the elements of the set {3,4,5,6,7,8,9}\{3, 4, 5, 6, 7, 8, 9\} yields a total of 77 values.

Anahtar Kavram

Triangle Inequality Theorem
Tahmini Süre:1m 30s
Soru 2446Soru

In the standard (x,y)(x, y) coordinate plane, a circular running track is modeled by the equation (x2)2+(y3)2=25(x - 2)^2 + (y - 3)^2 = 25. A straight pathway, modeled by the line y=2x1y = 2x - 1, cuts through the track. What is the distance, in coordinate units, between the two points where the pathway intersects the track?

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Cevap: 1010

Cevap

The distance between the two intersection points is 1010.
The circle (x2)2+(y3)2=25(x - 2)^2 + (y - 3)^2 = 25 has a center of (2,3)(2, 3) and a radius of r=5r = 5. Since the line y=2x1y = 2x - 1 passes through (2,3)(2, 3), the line contains a diameter of the circle. The distance between the two intersection points is therefore the diameter of the circle, which is 2r=102r = 10.

Adım Adım Çözüm

1
Identify the center and radius of the circle from its equation (x2)2+(y3)2=25(x - 2)^2 + (y - 3)^2 = 25.
The center is (2,3)(2, 3) and the radius is r=25=5r = \sqrt{25} = 5.
To understand the geometry of the circle and find its radius.
2
Determine if the line y=2x1y = 2x - 1 passes through the center of the circle (2,3)(2, 3) by substituting the coordinates into the equation.
3=2(2)1    3=33 = 2(2) - 1 \implies 3 = 3, which is true.
If the line passes through the center, the distance between the intersection points is simply the diameter of the circle.
3
Calculate the diameter of the circle.
Diameter=2r=2(5)=10\text{Diameter} = 2r = 2(5) = 10.
The distance between two opposite points on a circle passing through the center is equal to the diameter.

Anahtar Kavram

Systems of Linear and Non-Linear Equations
Soru 2447Soru

The quadratic equation 0.4x22x+c=00.4x^2 - 2x + c = 0 has two real solutions. If the difference between these two solutions is exactly 33, what is the value of cc?

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Cevap: 1.6

Cevap

1.6
By using the relation between the roots of a quadratic equation ax2+bx+c=0ax^2 + bx + c = 0, we find that the difference of the roots is given by x1x2=b24aca|x_1 - x_2| = \frac{\sqrt{b^2 - 4ac}}{|a|}. Substituting a=0.4a = 0.4, b=2b = -2, and the difference of 33 yields 3=41.6c0.43 = \frac{\sqrt{4 - 1.6c}}{0.4}. Multiplying by 0.40.4 and squaring both sides gives 1.44=41.6c1.44 = 4 - 1.6c. Solving this linear equation gives c=1.6c = 1.6. We can verify this result by substituting c=1.6c = 1.6 back into the original equation: 0.4x22x+1.6=00.4x^2 - 2x + 1.6 = 0 simplifies to x25x+4=0x^2 - 5x + 4 = 0, which factors as (x1)(x4)=0(x-1)(x-4) = 0. The roots are 11 and 44, and their difference is 41=34 - 1 = 3.

Adım Adım Çözüm

1
Identify the coefficients of the quadratic equation.
a=0.4a = 0.4, b=2b = -2, and the constant term is cc.
To apply formulas relating the roots to the coefficients of the equation.
2
Apply the formula for the difference of the roots.
x1x2=b24aca|x_1 - x_2| = \frac{\sqrt{b^2 - 4ac}}{|a|}
The problem states the difference between the two solutions is 33.
3
Substitute the known values into the formula and solve.
3=(2)24(0.4)c0.41.2=41.6c3 = \frac{\sqrt{(-2)^2 - 4(0.4)c}}{0.4} \Rightarrow 1.2 = \sqrt{4 - 1.6c}
To isolate the square root expression containing the unknown variable.
4
Square both sides and solve the linear equation for cc.
1.44=41.6c1.6c=2.56c=1.61.44 = 4 - 1.6c \Rightarrow 1.6c = 2.56 \Rightarrow c = 1.6
To eliminate the square root and find the value of cc.

Anahtar Kavram

Quadratic Equations and the Quadratic Formula
Tahmini Süre:1m 30s
Soru 2448Soru

A rectangular swimming pool has a length of 3x23x - 2 meters and a width of 2x52x - 5 meters. A concrete walkway with a uniform width of 22 meters surrounds the pool. Which of the following expressions represents the area, in square meters, of the walkway?

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Cevap: 20x1220x - 12

Cevap

The expression representing the area of the walkway is 20x1220x - 12.
The correct answer is the expression 20x1220x - 12. The total area including the walkway is (3x+2)(2x1)=6x2+x2(3x + 2)(2x - 1) = 6x^2 + x - 2. The pool's area is (3x2)(2x5)=6x219x+10(3x - 2)(2x - 5) = 6x^2 - 19x + 10. Subtracting the pool's area from the total area and distributing the negative sign to all terms gives: (6x2+x2)(6x219x+10)=6x2+x26x2+19x10=20x12(6x^2 + x - 2) - (6x^2 - 19x + 10) = 6x^2 + x - 2 - 6x^2 + 19x - 10 = 20x - 12.

Adım Adım Çözüm

1
Determine the dimensions of the entire area including the pool and the walkway.
The total length is (3x2)+2(2)=3x+2(3x - 2) + 2(2) = 3x + 2 meters, and the total width is (2x5)+2(2)=2x1(2x - 5) + 2(2) = 2x - 1 meters.
Since the walkway surrounds the pool on all sides, we add twice the width of the walkway to both the length and width of the pool.
2
Calculate the total area including the walkway.
Total Area = (3x+2)(2x1)=6x23x+4x2=6x2+x2(3x + 2)(2x - 1) = 6x^2 - 3x + 4x - 2 = 6x^2 + x - 2 square meters.
The area is found by multiplying the total length and the total width using binomial multiplication.
3
Calculate the area of the pool itself.
Pool Area = (3x2)(2x5)=6x215x4x+10=6x219x+10(3x - 2)(2x - 5) = 6x^2 - 15x - 4x + 10 = 6x^2 - 19x + 10 square meters.
The area of the pool is the product of its length and width.
4
Subtract the pool area from the total area to find the area of the walkway.
Walkway Area = (6x2+x2)(6x219x+10)=6x2+x26x2+19x10=20x12(6x^2 + x - 2) - (6x^2 - 19x + 10) = 6x^2 + x - 2 - 6x^2 + 19x - 10 = 20x - 12 square meters.
Subtracting the inner pool area from the total area yields the remaining area of the walkway surrounding it.

Anahtar Kavram

Calculating the difference between two binomial products to find the area of a border.
Soru 2449Soru

For a certain four-sided convex polygon, the ratio of its interior angle measures is 1:2:3:41:2:3:4. What is the degree measure of the smallest angle?

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Cevap: 3636^\circ

Cevap

3636^\circ
The correct answer is 3636^\circ because the sum of the interior angles of a four-sided polygon is 360360^\circ. The ratio 1:2:3:41:2:3:4 means the angles can be represented as xx, 2x2x, 3x3x, and 4x4x. Their sum is 10x=36010x = 360^\circ, which yields x=36x = 36^\circ. The smallest angle is xx, which is 3636^\circ.

Adım Adım Çözüm

1
Determine the sum of the interior angles of a four-sided convex polygon.
The sum of the interior angles of a four-sided polygon is 360360^\circ.
The sum of the interior angles of a polygon with nn sides is given by the formula (n2)×180(n-2) \times 180^\circ. For a four-sided polygon, (42)×180=360(4-2) \times 180^\circ = 360^\circ.
2
Find the sum of the parts of the given ratio.
1+2+3+4=101 + 2 + 3 + 4 = 10 parts
To distribute the total angle measure proportionally, the individual parts of the ratio 1:2:3:41:2:3:4 must be summed.
3
Calculate the measure of one part of the ratio.
360÷10=36360^\circ \div 10 = 36^\circ
Dividing the total sum of the interior angles by the total number of parts determines the degree measure of a single part.
4
Find the measure of the smallest angle.
1×36=361 \times 36^\circ = 36^\circ
The smallest angle corresponds to the smallest part of the ratio, which is 1.

Anahtar Kavram

The sum of the interior angles of a convex polygon with nn sides is (n2)×180(n-2) \times 180^\circ, and this total can be divided proportionally using a given ratio to find individual angle measures.
Tahmini Süre:1m 0s
Soru 2450Soru

In the standard (x,y)(x, y) coordinate plane, a circle is tangent to the xx-axis at the point (5,0)(5, 0). If the circle is also tangent to the line y=43xy = \frac{4}{3}x and its center lies in the first quadrant, what is the yy-coordinate of the center of the circle?

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Cevap: 2.5

Cevap

The yy-coordinate of the center of the circle is 2.52.5.
A circle tangent to the xx-axis at (5,0)(5, 0) has a center along the vertical line x=5x = 5. Since the center is in the first quadrant, its coordinates can be represented as (5,k)(5, k) where k>0k > 0, and the radius is kk. The distance from the center (5,k)(5, k) to the line 4x3y=04x - 3y = 0 must also equal the radius kk. Using the point-to-line distance formula, we write 4(5)3k42+(3)2=k\frac{|4(5) - 3k|}{\sqrt{4^2 + (-3)^2}} = k, which simplifies to 203k=5k|20 - 3k| = 5k. Since the center must lie in the first quadrant (k>0k > 0), we solve 203k=5k20 - 3k = 5k to find k=2.5k = 2.5. The alternative case 203k=5k20 - 3k = -5k gives k=10k = -10, which lies in the fourth quadrant and is thus excluded.

Adım Adım Çözüm

1
Identify the coordinates of the center and the radius of the circle based on the xx-axis tangency.
Center: (5,k)(5, k) and Radius: r=kr = k (where k>0k > 0).
A circle tangent to the xx-axis at (5,0)(5, 0) has its center directly above or below this point on the line x=5x = 5. Since the center is in the first quadrant, its yy-coordinate kk must be positive, making the radius kk.
2
Use the distance from the center to the second tangent line to write an equation for kk.
4(5)3k42+(3)2=k\frac{|4(5) - 3k|}{\sqrt{4^2 + (-3)^2}} = k
The distance from the center (5,k)(5, k) to the tangent line 4x3y=04x - 3y = 0 must equal the radius of the circle.
3
Simplify the equation and solve for kk.
203k=5k|20 - 3k| = 5k, leading to k=2.5k = 2.5 or k=10k = -10.
Simplifying the denominator yields 55. Multiplying both sides by 55 gives the absolute value equation, which resolves to 203k=5k20 - 3k = 5k or 203k=5k20 - 3k = -5k.
4
Select the valid solution using the quadrant constraint.
k=2.5k = 2.5
The center must lie in the first quadrant, which requires k>0k > 0. Thus, k=10k = -10 is discarded, and the correct value is 2.52.5.

Anahtar Kavram

The relationship between a circle's center, its radius, and its tangent lines in the coordinate plane.
Soru 2451Soru

A rectangular piece of paper ABCDABCD has dimensions AB=12AB = 12 inches and BC=9BC = 9 inches. The paper is folded so that vertex AA falls directly on vertex CC, creating a crease EFEF where EE lies on ABAB and FF lies on CDCD. What is the length of the crease EFEF, in inches?

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Cevap: 11.25

Cevap

The length of the crease is 11.25 inches.
By interpreting the fold geometrically, we establish that the crease is the perpendicular bisector of the diagonal. We can solve for the segments along the side using a right triangle formed at the corner, and then construct a second right triangle using an altitude to find the length of the crease hypotenuse.

Adım Adım Çözüm

1
Identify the relationship created by the fold.
The crease EFEF is the perpendicular bisector of the diagonal ACAC, meaning AE=EC=xAE = EC = x.
When a point is folded onto another, the crease line acts as the perpendicular bisector of the segment connecting the two points.
2
Set up an expression for the remaining part of the side ABAB.
Since AB=12AB = 12 and AE=xAE = x, the length of EB=12xEB = 12 - x.
The point EE lies on segment ABAB, dividing it into AEAE and EBEB.
3
Use the Pythagorean Theorem in right triangle EBCEBC to solve for xx.
x2=(12x)2+92    x2=14424x+x2+81    24x=225    x=9.375x^2 = (12 - x)^2 + 9^2 \implies x^2 = 144 - 24x + x^2 + 81 \implies 24x = 225 \implies x = 9.375.
The triangle EBCEBC is a right triangle with legs EBEB and BCBC, and hypotenuse ECEC.
4
Form a second right triangle to find the length of the crease EFEF.
Draw FGABFG \perp AB with GG on ABAB. This forms right triangle EGFEGF with legs FG=9FG = 9 and EG=ABEBDF=122.6252.625=6.75EG = AB - EB - DF = 12 - 2.625 - 2.625 = 6.75.
Constructing an altitude from FF to ABAB allows us to create a right triangle that has the crease EFEF as its hypotenuse.
5
Apply the Pythagorean Theorem to right triangle EGFEGF to calculate the final length of EFEF.
EF=6.752+92=45.5625+81=126.5625=11.25EF = \sqrt{6.75^2 + 9^2} = \sqrt{45.5625 + 81} = \sqrt{126.5625} = 11.25 inches.
The hypotenuse of right triangle EGFEGF represents the length of the crease.

Anahtar Kavram

Applying the Pythagorean Theorem to geometric folds and multi-step right triangle relationships
Soru 2452Soru

On a map of a town laid out on a standard coordinate grid, a straight path has an xx-intercept of 6-6 and a yy-intercept of 44. A landmark is located on this path at a point where the xx-coordinate is 99. What is the yy-coordinate of the landmark?

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Cevap: 10

Cevap

The yy-coordinate of the landmark is 10.
The correct answer is 10. The linear path passes through the points (6,0)(-6, 0) and (0,4)(0, 4). Using the slope formula, the slope is m=400(6)=23m = \frac{4 - 0}{0 - (-6)} = \frac{2}{3}. The slope-intercept equation of the line is y=23x+4y = \frac{2}{3}x + 4. Substituting the landmark's xx-coordinate of 99 into the equation gives y=23(9)+4=10y = \frac{2}{3}(9) + 4 = 10.

Adım Adım Çözüm

1
Identify the coordinates of the points representing the intercepts on the coordinate grid.
The points are (6,0)(-6, 0) and (0,4)(0, 4).
An xx-intercept of 6-6 corresponds to the coordinate point (6,0)(-6, 0), and a yy-intercept of 44 corresponds to the coordinate point (0,4)(0, 4).
2
Calculate the slope of the linear path.
The slope is 23\frac{2}{3}.
Using the slope formula m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1}, substitute the points (6,0)(-6, 0) and (0,4)(0, 4) to get m=400(6)=46=23m = \frac{4 - 0}{0 - (-6)} = \frac{4}{6} = \frac{2}{3}.
3
Write the linear equation representing the path.
The equation is y=23x+4y = \frac{2}{3}x + 4.
With a slope of m=23m = \frac{2}{3} and a yy-intercept of b=4b = 4, the equation in slope-intercept form (y=mx+by = mx + b) is y=23x+4y = \frac{2}{3}x + 4.
4
Find the yy-coordinate of the landmark by substituting its xx-coordinate.
The yy-coordinate is 10.
Substitute x=9x = 9 into the equation: y=23(9)+4=6+4=10y = \frac{2}{3}(9) + 4 = 6 + 4 = 10.

Anahtar Kavram

Linear Equations and Graphing
Soru 2453Soru

The position of a particle moving along a straight line is described by the polynomial s(t)=(2t23t+4)(t+3)s(t) = (2t^2 - 3t + 4)(t + 3), where tt represents the time in seconds and s(t)s(t) represents the displacement in meters. When the polynomial is expanded and written in the standard form at3+bt2+ct+dat^3 + bt^2 + ct + d, what is the value of b+cb + c?

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Cevap: -2

Cevap

The value of b+cb + c is 2-2.
Expanding the polynomial s(t)=(2t23t+4)(t+3)s(t) = (2t^2 - 3t + 4)(t + 3) yields 2t3+3t25t+122t^3 + 3t^2 - 5t + 12. Comparing this to the standard form at3+bt2+ct+dat^3 + bt^2 + ct + d, we find b=3b = 3 and c=5c = -5. Summing these coefficients gives b+c=3+(5)=2b + c = 3 + (-5) = -2.

Adım Adım Çözüm

1
Multiply each term of the trinomial 2t23t+42t^2 - 3t + 4 by each term of the binomial t+3t + 3.
2t3+6t23t29t+4t+122t^3 + 6t^2 - 3t^2 - 9t + 4t + 12
Apply the distributive property to expand the product of the polynomials.
2
Combine the like terms (the t2t^2 terms and the tt terms).
2t3+3t25t+122t^3 + 3t^2 - 5t + 12
Group and add the coefficients of like terms to simplify the polynomial.
3
Identify the coefficients bb (for the t2t^2 term) and cc (for the tt term) and find their sum.
b=3b = 3 and c=5c = -5, so b+c=3+(5)=2b + c = 3 + (-5) = -2
Compare the simplified polynomial to the standard form at3+bt2+ct+dat^3 + bt^2 + ct + d to find the coefficients, then calculate the requested sum.

Anahtar Kavram

Operations on Polynomials

Alternatif Yöntem

Instead of expanding the whole expression, you can find the individual coefficients directly. The t2t^2 term is formed by (2t2)(3)+(3t)(t)=6t23t2=3t2(2t^2)(3) + (-3t)(t) = 6t^2 - 3t^2 = 3t^2, so b=3b = 3. The tt term is formed by (3t)(3)+(4)(t)=9t+4t=5t(-3t)(3) + (4)(t) = -9t + 4t = -5t, so c=5c = -5. Thus, b+c=35=2b + c = 3 - 5 = -2.
Tahmini Süre:1m 30s
Soru 2454Soru

For the quadratic equation 1.5x25x+c=01.5x^2 - 5x + c = 0, where cc is a real constant, the equation has two non-real complex solutions. Which of the following inequalities represents all possible values of cc?

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Cevap: c>256c > \frac{25}{6}

Cevap

c>256c > \frac{25}{6}
For a quadratic equation to have two non-real complex solutions, its discriminant must be negative. Substituting a=1.5a = 1.5, b=5b = -5, and the constant cc into the discriminant formula b24ac<0b^2 - 4ac < 0 gives 256c<025 - 6c < 0. Solving this inequality results in the requirement that the constant must be strictly greater than twenty-five sixths.

Adım Adım Çözüm

1
Identify the coefficients of the quadratic equation 1.5x25x+c=01.5x^2 - 5x + c = 0 in the standard form ax2+bx+c=0ax^2 + bx + c = 0.
a=1.5a = 1.5, b=5b = -5, and c=cc = c.
These coefficients are required to compute the discriminant.
2
Set up the condition for the quadratic equation to have two non-real complex solutions using the discriminant Δ=b24ac\Delta = b^2 - 4ac.
The discriminant must be strictly negative: (5)24(1.5)(c)<0(-5)^2 - 4(1.5)(c) < 0.
A quadratic equation has non-real complex solutions if and only if its discriminant is negative.
3
Simplify the inequality and solve for cc.
256c<0    25<6c    c>25625 - 6c < 0 \implies 25 < 6c \implies c > \frac{25}{6}.
Isolating cc yields the range of values that satisfy the condition.

Anahtar Kavram

A quadratic equation ax2+bx+c=0ax^2 + bx + c = 0 has two non-real complex solutions if and only if its discriminant, Δ=b24ac\Delta = b^2 - 4ac, is strictly less than zero.
Tahmini Süre:1m 30s
Soru 2455Soru

Points K(2,5)K(-2, 5) and L(6,1)L(6, -1) are the endpoints of segment KLKL on a coordinate plane. What is the distance from the midpoint of segment KLKL to the point P(5,7)P(5, 7)?

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Cevap: 34\sqrt{34}

Cevap

The correct answer is the square root of 34.
To find the distance from the midpoint of segment KLKL to the point P(5,7)P(5, 7), we first calculate the midpoint MM of KLKL. Using the midpoint formula, the coordinates are x=2+62=2x = \frac{-2 + 6}{2} = 2 and y=5+(1)2=2y = \frac{5 + (-1)}{2} = 2, giving M(2,2)M(2, 2). Next, we apply the distance formula to find the distance between M(2,2)M(2, 2) and P(5,7)P(5, 7), which is d=(52)2+(72)2=32+52=9+25=34d = \sqrt{(5 - 2)^2 + (7 - 2)^2} = \sqrt{3^2 + 5^2} = \sqrt{9 + 25} = \sqrt{34}. This confirms the correct distance is the square root of 34.

Adım Adım Çözüm

1
Calculate the coordinates of the midpoint of segment KLKL using the midpoint formula: M=(x1+x22,y1+y22)M = \left(\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2}\right).
The midpoint is M(2,2)M(2, 2) since x=2+62=2x = \frac{-2 + 6}{2} = 2 and y=5+(1)2=2y = \frac{5 + (-1)}{2} = 2.
Finding the midpoint of the segment is required before finding the distance from it to point PP.
2
Calculate the distance between the midpoint M(2,2)M(2, 2) and the point P(5,7)P(5, 7) using the distance formula: d=(x2x1)2+(y2y1)2d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}.
The distance is 34\sqrt{34} since d=(52)2+(72)2=32+52=9+25=34d = \sqrt{(5 - 2)^2 + (7 - 2)^2} = \sqrt{3^2 + 5^2} = \sqrt{9 + 25} = \sqrt{34}.
This determines the final distance required by the question.

Anahtar Kavram

Applying both the midpoint and distance formulas sequentially to solve coordinate geometry problems.
Soru 2456Soru

In PQR\triangle PQR, the measure of P\angle P is 5050^\circ. The angle bisectors of PQR\angle PQR and PRQ\angle PRQ intersect at point II inside the triangle. What is the measure of QIR\angle QIR?

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Cevap: 115115^\circ

Cevap

115 degrees
To find the measure of the angle at the intersection, we first use the Triangle Angle-Sum Theorem on the larger triangle. The sum of the interior angles in the larger triangle is 180 degrees. Since the angle at one vertex is 50 degrees, the sum of the other two angles must be 130 degrees. The angle bisectors divide these two angles in half, meaning the sum of the two half-angles in the smaller triangle is half of 130 degrees, which is 65 degrees. Applying the Triangle Angle-Sum Theorem to the smaller triangle, the sum of its interior angles is also 180 degrees. Subtracting the sum of the two half-angles (65 degrees) from 180 degrees gives 115 degrees for the angle at the intersection.

Adım Adım Çözüm

1
Find the sum of the remaining interior angles of the triangle.
The sum of the angles at Q and R is 130 degrees.
The sum of all interior angles in any triangle is always 180 degrees, and the angle at P is given as 50 degrees.
2
Determine the sum of the bisected angles in the smaller triangle.
The sum of the half-angles is 65 degrees.
Since the lines QI and RI are angle bisectors, the sum of the interior angles of the smaller triangle at vertices Q and R is half the sum of the angles at Q and R of the larger triangle.
3
Calculate the measure of the angle at the intersection point.
The angle at the intersection point is 115 degrees.
The sum of the interior angles in the smaller triangle is also 180 degrees, so the unknown angle is found by subtracting the sum of the two half-angles from 180 degrees.

Anahtar Kavram

The Triangle Angle-Sum Theorem states that the sum of the measures of the interior angles of a triangle is always 180 degrees. Angle bisectors divide an angle into two equal parts.

Alternatif Yöntem

Alternatively, one can assign specific values to the angles that satisfy the given conditions. Since the sum of the angles in the large triangle must be 180 degrees and the angle at vertex P is 50 degrees, the sum of the other two angles must be 130 degrees. If we assume the triangle is isosceles with the two unknown angles being equal, each of those angles is 65 degrees. Their bisectors would each form an angle of 32.5 degrees with the base. In the smaller triangle, the sum of these two bisected angles is 65 degrees, which leaves 115 degrees for the angle at the intersection point.
Tahmini Süre:1m 15s
Soru 2457Soru

In parallelogram ABCDABCD, the measure of interior angle AA is 7272^\circ. What is the measure, in degrees, of interior angle BB?

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Cevap: 108

Cevap

The measure of interior angle BB is 108108 degrees.
In parallelogram ABCDABCD, interior angles AA and BB are consecutive angles. A fundamental property of parallelograms is that consecutive angles are supplementary (their measures sum to 180180^\circ). Therefore, the measure of angle BB is calculated as 18072=108180^\circ - 72^\circ = 108^\circ.

Adım Adım Çözüm

1
Use the consecutive angles property of parallelograms.
The sum of consecutive interior angles AA and BB is 180180^\circ.
Since opposite sides of a parallelogram are parallel, consecutive interior angles are supplementary.
2
Set up the equation and solve for the unknown angle.
mB=108m\angle B = 108^\circ
Subtract 7272^\circ from 180180^\circ.

Anahtar Kavram

Properties of parallelograms (consecutive angles are supplementary)
Soru 2458Soru

A square in the standard (x,y)(x, y) coordinate plane has vertices at A(1,1)A(1, 1), B(3,1)B(3, 1), C(3,3)C(3, 3), and D(1,3)D(1, 3). The square is dilated by a scale factor of 33 with the center of dilation at point A(1,1)A(1, 1). The resulting image is then translated 22 units left and 44 units up. What are the coordinates of the final image of vertex CC?

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Cevap: (5,11)(5, 11)

Cevap

The final coordinates of the image of vertex CC are (5,11)(5, 11).
To find the coordinates of the image of vertex C(3,3)C(3, 3) after the dilation, we calculate the horizontal and vertical distances from the center of dilation A(1,1)A(1, 1) to C(3,3)C(3, 3). Both distances are 22 units. Since the scale factor is 33, these distances are tripled to 66 units. Adding these to the coordinates of the center A(1,1)A(1, 1) gives the dilated point (1+6,1+6)=(7,7)(1 + 6, 1 + 6) = (7, 7). Next, we apply the translation of 22 units left (subtracting 22 from the xx-coordinate) and 44 units up (adding 44 to the yy-coordinate) to (7,7)(7, 7), which yields the final coordinates (72,7+4)=(5,11)(7 - 2, 7 + 4) = (5, 11).

Adım Adım Çözüm

1
Find the coordinates of the image of vertex C(3,3)C(3, 3) after a dilation with scale factor 33 centered at A(1,1)A(1, 1).
The coordinates after dilation are (7,7)(7, 7).
The horizontal and vertical distances from the center A(1,1)A(1, 1) to C(3,3)C(3, 3) are both 22 units (31=23 - 1 = 2). Multiplying these distances by the scale factor of 33 yields 66 units. Adding these new distances to the coordinates of the center A(1,1)A(1, 1) gives (1+6,1+6)=(7,7)(1 + 6, 1 + 6) = (7, 7).
2
Apply a translation of 22 units left and 44 units up to the point (7,7)(7, 7).
The final coordinates are (5,11)(5, 11).
Translating 22 units left subtracts 22 from the xx-coordinate (72=57 - 2 = 5). Translating 44 units up adds 44 to the yy-coordinate (7+4=117 + 4 = 11).

Anahtar Kavram

Transformations in the Coordinate Plane
Tahmini Süre:1m 30s
Soru 2459Soru

In the right trapezoid ABCDABCD below, ABAB is parallel to CDCD, and the measures of A\angle A and D\angle D are both 9090^\circ. The length of CDCD is 77, the length of BCBC is 88, and the measure of B\angle B is 6060^\circ. What is the length of the diagonal BDBD?

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Cevap: 13

Cevap

13
By drawing altitude CECE perpendicular to ABAB, we form rectangle AECDAECD and right triangle CEB\triangle CEB. Since B=60\angle B = 60^\circ, CEB\triangle CEB is a 3030^\circ-6060^\circ-9090^\circ triangle with hypotenuse BC=8BC = 8. The side opposite 3030^\circ is BE=8/2=4BE = 8/2 = 4, and the side opposite 6060^\circ is CE=43CE = 4\sqrt{3}. Since opposite sides of rectangle AECDAECD are equal, we find AD=CE=43AD = CE = 4\sqrt{3} and AE=CD=7AE = CD = 7. Thus, AB=AE+BE=7+4=11AB = AE + BE = 7 + 4 = 11. Finally, we apply the Pythagorean Theorem to right triangle DAB\triangle DAB: BD2=AD2+AB2=(43)2+112=48+121=169BD^2 = AD^2 + AB^2 = (4\sqrt{3})^2 + 11^2 = 48 + 121 = 169, yielding BD=13BD = 13.

Adım Adım Çözüm

1
Decompose the trapezoid by drawing an altitude from CC perpendicular to ABAB, meeting it at EE.
This forms a rectangle AECDAECD and a right triangle CEBCEB.
Decomposing the figure allows us to use right triangle trigonometry and parallel line relationships to determine missing side lengths.
2
Calculate the lengths of the legs of right triangle CEBCEB.
BE=4BE = 4 and CE=43CE = 4\sqrt{3}.
Since B=60\angle B = 60^\circ, CEB\triangle CEB is a 3030^\circ-6060^\circ-9090^\circ triangle. The shorter leg BEBE is half the hypotenuse BCBC, and the longer leg CECE is the shorter leg times 3\sqrt{3}.
3
Determine the lengths of ADAD and ABAB.
AD=43AD = 4\sqrt{3} and AB=11AB = 11.
In the rectangle AECDAECD, opposite sides are equal, so AD=CE=43AD = CE = 4\sqrt{3} and AE=CD=7AE = CD = 7. Thus, the base AB=AE+BE=7+4=11AB = AE + BE = 7 + 4 = 11.
4
Use the Pythagorean Theorem in right triangle DABDAB to solve for BDBD.
BD=13BD = 13.
In right triangle DABDAB, the legs are AD=43AD = 4\sqrt{3} and AB=11AB = 11. The hypotenuse BDBD satisfies BD2=AD2+AB2=(43)2+112=48+121=169BD^2 = AD^2 + AB^2 = (4\sqrt{3})^2 + 11^2 = 48 + 121 = 169, so BD=169=13BD = \sqrt{169} = 13.

Anahtar Kavram

Solving multi-step geometry problems by decomposing shapes into rectangles and special right triangles (3030^\circ-6060^\circ-9090^\circ), then applying the Pythagorean Theorem.
Soru 2460Soru

A convex hexagon has four interior angles that measure 100100^\circ, 115115^\circ, 125125^\circ, and 140140^\circ. The remaining two interior angles are in the ratio 3:53:5. What is the degree measure of the largest interior angle of this hexagon?

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Cevap: 150150^\circ

Cevap

The degree measure of the largest interior angle is 150150^\circ.
The sum of the interior angles of a hexagon is (62)×180=720(6-2) \times 180^\circ = 720^\circ. Subtracting the four given angles (100100^\circ, 115115^\circ, 125125^\circ, and 140140^\circ) from 720720^\circ leaves a remaining sum of 240240^\circ. Since the two remaining angles are in the ratio 3:53:5, they can be written as 3x3x and 5x5x, where 3x+5x=2403x + 5x = 240^\circ. Solving for xx gives 8x=240    x=308x = 240^\circ \implies x = 30^\circ. The two remaining angles are 9090^\circ and 150150^\circ. Comparing all six interior angles of the hexagon, the largest measure is 150150^\circ.

Adım Adım Çözüm

1
Calculate the sum of the interior angles of a hexagon.
The sum is (62)×180=720(6-2) \times 180^\circ = 720^\circ.
The sum of the interior angles of any convex nn-sided polygon is given by (n2)×180(n-2) \times 180^\circ.
2
Find the sum of the four given interior angles.
100+115+125+140=480100^\circ + 115^\circ + 125^\circ + 140^\circ = 480^\circ.
This determines the total measure of the known angles.
3
Determine the remaining sum of the two unknown angles.
720480=240720^\circ - 480^\circ = 240^\circ.
Subtracting the sum of the known angles from the total sum yields the combined measure of the remaining two angles.
4
Set up an equation using the ratio 3:53:5 to find the measures of the two remaining angles.
3x+5x=240    8x=240    x=303x + 5x = 240^\circ \implies 8x = 240^\circ \implies x = 30^\circ. The two angles are 3(30)=903(30^\circ) = 90^\circ and 5(30)=1505(30^\circ) = 150^\circ.
Representing the two angles in terms of a common variable xx allows us to solve for their individual measures.
5
Identify the largest interior angle among all six angles of the hexagon.
The largest angle is 150150^\circ.
Comparing all six angles (9090^\circ, 100100^\circ, 115115^\circ, 125125^\circ, 140140^\circ, and 150150^\circ), the maximum value is 150150^\circ.

Anahtar Kavram

Calculating the interior angle sum of a polygon and solving for unknown angles using ratios.
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