Tüm alıştırma soruları

2131 soru

Soru 1421Soru

Two concentric circles centered at point OO have radii rr and RR, where r<Rr < R. A sector bounded by radii OAOA and OBOB of the outer circle has central angle θ\theta^\circ. Region SS is the region lying inside sector AOBAOB but outside the inner circle. The area of region SS is equal to 33 times the area of the sector of the inner circle bounded by central angle θ\theta^\circ. If the perimeter of region SS is equal to 116\frac{11}{6} times the length of arc ABAB, what is the value of θ\theta?

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Cevap: 540π\frac{540}{\pi}

Cevap

540π\frac{540}{\pi}
The area of region SS is θ360π(R2r2)\frac{\theta}{360}\pi(R^2 - r^2), which is equal to 33 times the area of the inner sector θ360πr2\frac{\theta}{360}\pi r^2. This simplifies to R2r2=3r2    R=2rR^2 - r^2 = 3r^2 \implies R = 2r. The perimeter of region SS consists of outer arc length LouterL_{\text{outer}}, inner arc length Linner=12LouterL_{\text{inner}} = \frac{1}{2} L_{\text{outer}}, and two straight line segments each of length Rr=rR - r = r. Setting the total perimeter 32Louter+2r\frac{3}{2} L_{\text{outer}} + 2r equal to 116Louter\frac{11}{6} L_{\text{outer}} yields 2r=13Louter2r = \frac{1}{3} L_{\text{outer}}, or Louter=6rL_{\text{outer}} = 6r. Substituting Louter=θ360(2πR)=4πrθ360L_{\text{outer}} = \frac{\theta}{360}(2\pi R) = \frac{4\pi r \theta}{360} gives 4πrθ360=6r\frac{4\pi r \theta}{360} = 6r, which solves to θ=540π\theta = \frac{540}{\pi}.

Adım Adım Çözüm

1
Relate outer radius RR to inner radius rr using sector areas.
R=2rR = 2r
The area of region SS is θ360π(R2r2)\frac{\theta}{360}\pi(R^2 - r^2) and the inner sector area is θ360πr2\frac{\theta}{360}\pi r^2. Setting θ360π(R2r2)=3θ360πr2\frac{\theta}{360}\pi(R^2 - r^2) = 3 \cdot \frac{\theta}{360}\pi r^2 gives R2r2=3r2R^2 - r^2 = 3r^2, so R2=4r2R^2 = 4r^2 and R=2rR = 2r.
2
Express the perimeter of region SS in terms of outer arc length LouterL_{\text{outer}} and radius rr.
Perimeter(S)=32Louter+2r\text{Perimeter}(S) = \frac{3}{2} L_{\text{outer}} + 2r
Region SS is bounded by outer arc ABAB (LouterL_{\text{outer}}), inner arc CDCD (LinnerL_{\text{inner}}), and two straight segments ACAC and BDBD of length Rr=2rr=rR - r = 2r - r = r. Since R=2rR = 2r, Linner=12LouterL_{\text{inner}} = \frac{1}{2} L_{\text{outer}}, making total perimeter Louter+12Louter+2(r)=32Louter+2rL_{\text{outer}} + \frac{1}{2} L_{\text{outer}} + 2(r) = \frac{3}{2} L_{\text{outer}} + 2r.
3
Use the given perimeter relationship to express LouterL_{\text{outer}} in terms of rr.
Louter=6rL_{\text{outer}} = 6r
Setting 32Louter+2r=116Louter\frac{3}{2} L_{\text{outer}} + 2r = \frac{11}{6} L_{\text{outer}} yields 2r=(11696)Louter=13Louter2r = \left(\frac{11}{6} - \frac{9}{6}\right) L_{\text{outer}} = \frac{1}{3} L_{\text{outer}}, so Louter=6rL_{\text{outer}} = 6r.
4
Solve for θ\theta using the definition of outer arc length.
θ=540π\theta = \frac{540}{\pi}
Louter=θ360(2πR)=θ360(4πr)L_{\text{outer}} = \frac{\theta}{360}(2\pi R) = \frac{\theta}{360}(4\pi r). Setting 4πrθ360=6r\frac{4\pi r \theta}{360} = 6r simplifies to πθ90=6\frac{\pi \theta}{90} = 6, giving θ=540π\theta = \frac{540}{\pi}.

Anahtar Kavram

Annular sector area and perimeter relations combining arc length formulas and concentric circle geometry.
Tahmini Süre:2m 30s
Soru 1422Soru

A circle has a radius of 99 inches. What is the area, in square inches, of a sector of this circle formed by a central angle of 4040^\circ?

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Cevap: 9π9\pi

Cevap

The area of the sector is 9π9\pi square inches.
The area of a sector with radius rr and central angle θ\theta is calculated as Area=πr2(θ360)\text{Area} = \pi r^2 \left(\frac{\theta}{360^\circ}\right). Substituting r=9r = 9 and θ=40\theta = 40^\circ yields π(92)(40360)=81π(19)=9π\pi (9^2) \left(\frac{40^\circ}{360^\circ}\right) = 81\pi \left(\frac{1}{9}\right) = 9\pi square inches.

Adım Adım Çözüm

1
Calculate the area of the entire circle using the formula Acircle=πr2A_{\text{circle}} = \pi r^2.
Acircle=π(92)=81πA_{\text{circle}} = \pi (9^2) = 81\pi square inches.
The full circle area provides the total measure from which the sector fraction is calculated.
2
Determine the fraction of the circle represented by the central angle of 4040^\circ.
40360=19\frac{40^\circ}{360^\circ} = \frac{1}{9}.
A circle contains 360360^\circ in total, so the central angle over 360360^\circ gives the proportion of the circle covered by the sector.
3
Multiply the total area of the circle by the fraction of the sector.
Sector Area=81π×19=9π\text{Sector Area} = 81\pi \times \frac{1}{9} = 9\pi square inches.
Applying the fraction to the total area yields the specific sector area.

Anahtar Kavram

Sector Area of a Circle
Soru 1423Soru

Circle C1C_1 has radius r1r_1 and Circle C2C_2 has radius r2r_2. An arc on Circle C1C_1 subtended by a central angle of θ1\theta_1^\circ has the exact same length as an arc on Circle C2C_2 subtended by a central angle of θ2\theta_2^\circ. The sector formed by this arc in Circle C1C_1 has an area of 54π54\pi, and the sector formed by this arc in Circle C2C_2 has an area of 36π36\pi. If θ1+θ2=150\theta_1 + \theta_2 = 150, what is the value of r1r_1?

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Cevap: 18

Cevap

The radius r1r_1 of Circle C1C_1 is 18.
Using the relationship A=12LrA = \frac{1}{2} L r, the ratio of the two sector areas gives r1r2=54π36π=1.5\frac{r_1}{r_2} = \frac{54\pi}{36\pi} = 1.5, so r2=23r1r_2 = \frac{2}{3} r_1. Expressing arc length as L=108πr1L = \frac{108\pi}{r_1}, the central angles are θ1=19440r12\theta_1 = \frac{19440}{r_1^2} and θ2=29160r12\theta_2 = \frac{29160}{r_1^2}. Setting their sum equal to 150150 leads to 48600r12=150\frac{48600}{r_1^2} = 150, giving r12=324r_1^2 = 324 and r1=18r_1 = 18.

Adım Adım Çözüm

1
Relate sector area to arc length and radius
A1=12Lr1=54πA_1 = \frac{1}{2} L r_1 = 54\pi and A2=12Lr2=36πA_2 = \frac{1}{2} L r_2 = 36\pi
The area of a sector with arc length LL and radius rr is given by A=θ360πr2=12LrA = \frac{\theta}{360}\pi r^2 = \frac{1}{2} L r.
2
Find the ratio of r1r_1 to r2r_2
r1r2=54π36π=32    r2=23r1\frac{r_1}{r_2} = \frac{54\pi}{36\pi} = \frac{3}{2} \implies r_2 = \frac{2}{3}r_1
Dividing the first area equation by the second cancels out 12L\frac{1}{2}L.
3
Express central angles in terms of r1r_1
θ1=19440r12\theta_1 = \frac{19440}{r_1^2} and θ2=29160r12\theta_2 = \frac{29160}{r_1^2}
Since L=108πr1L = \frac{108\pi}{r_1}, substituting into θ1=L2πr1×360\theta_1 = \frac{L}{2\pi r_1} \times 360 yields θ1=19440r12\theta_1 = \frac{19440}{r_1^2}, and substituting into θ2=L2π(23r1)×360\theta_2 = \frac{L}{2\pi (\frac{2}{3}r_1)} \times 360 yields θ2=29160r12\theta_2 = \frac{29160}{r_1^2}.
4
Solve for r1r_1 using the angle sum equation
r1=18r_1 = 18
Summing the angles gives 19440+29160r12=48600r12=150    r12=324    r1=18\frac{19440 + 29160}{r_1^2} = \frac{48600}{r_1^2} = 150 \implies r_1^2 = 324 \implies r_1 = 18.

Anahtar Kavram

Relationship between arc length, radius, central angle, and sector area
Tahmini Süre:2m 30s
Soru 1424Soru

If xx and yy are real numbers that satisfy the inequalities 32x9|3 - 2x| \le 9 and 4y+313|4y + 3| \le 13, what is the maximum possible value of the expression 3x4y|3x - 4y|?

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Cevap: 34

Cevap

The maximum possible value of 3x4y|3x - 4y| is 3434.
To find the maximum possible value of 3x4y|3x - 4y|, we first solve for the ranges of xx and yy from their respective absolute value inequalities. From 32x9|3 - 2x| \le 9, we get 932x9    3x6-9 \le 3 - 2x \le 9 \implies -3 \le x \le 6. From 4y+313|4y + 3| \le 13, we get 134y+313    4y2.5-13 \le 4y + 3 \le 13 \implies -4 \le y \le 2.5. To maximize 3x4y3x - 4y, we take the maximum value of 3x3x (3×6=183 \times 6 = 18) and the maximum value of 4y-4y (4×4=16-4 \times -4 = 16), giving 18+16=3418 + 16 = 34. To minimize 3x4y3x - 4y, we take the minimum value of 3x3x (3×3=93 \times -3 = -9) and the minimum value of 4y-4y (4×2.5=10-4 \times 2.5 = -10), giving 910=19-9 - 10 = -19. The expression 3x4y3x - 4y ranges from 19-19 to 3434, so the maximum possible magnitude 3x4y|3x - 4y| is max(19,34)=34\max(|-19|, |34|) = 34.

Adım Adım Çözüm

1
Solve the inequality 32x9|3 - 2x| \le 9 for xx.
3x6-3 \le x \le 6
Unpacking the absolute value yields 932x9-9 \le 3 - 2x \le 9. Subtracting 33 gives 122x6-12 \le -2x \le 6. Dividing by 2-2 and reversing the inequality signs produces 3x6-3 \le x \le 6.
2
Solve the inequality 4y+313|4y + 3| \le 13 for yy.
4y2.5-4 \le y \le 2.5
Unpacking the absolute value yields 134y+313-13 \le 4y + 3 \le 13. Subtracting 33 gives 164y10-16 \le 4y \le 10. Dividing by 44 gives 4y2.5-4 \le y \le 2.5.
3
Find the range of possible values for 3x3x and 4y-4y.
93x18-9 \le 3x \le 18 and 104y16-10 \le -4y \le 16
Multiplying 3x6-3 \le x \le 6 by 33 gives 93x18-9 \le 3x \le 18. Multiplying 4y2.5-4 \le y \le 2.5 by 4-4 and flipping the signs gives 104y16-10 \le -4y \le 16.
4
Combine the bounds for 3x3x and 4y-4y to find the range for 3x4y3x - 4y.
193x4y34-19 \le 3x - 4y \le 34
The minimum value of 3x4y3x - 4y is (9)+(10)=19(-9) + (-10) = -19. The maximum value of 3x4y3x - 4y is 18+16=3418 + 16 = 34.
5
Determine the maximum absolute value 3x4y|3x - 4y| over the interval [19,34][-19, 34].
34
The absolute value of any number in the interval [19,34][-19, 34] ranges from 00 to max(19,34)=34\max(|-19|, |34|) = 34.

Anahtar Kavram

Absolute Value Inequalities and Expression Bounding
Soru 1425Soru

In triangle ABCABC, the measure of angle AA is 4040^\circ and the measure of angle BB is 7070^\circ. If the perimeter of triangle ABCABC is 2222 centimeters and the length of side ABAB is 88 centimeters, what is the length, in centimeters, of side BCBC?

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Cevap: 66

Cevap

6 centimeters
First, find the measure of angle CC: 1804070=70180^\circ - 40^\circ - 70^\circ = 70^\circ. Because angle BB and angle CC both measure 7070^\circ, triangle ABCABC is isosceles with sides ACAC and ABAB of equal length (AC=AB=8AC = AB = 8 cm). Since the perimeter is the sum of all three sides (AB+AC+BC=22AB + AC + BC = 22), substituting the known side lengths gives 8+8+BC=228 + 8 + BC = 22, which yields BC=6BC = 6 cm.

Adım Adım Çözüm

1
Calculate the measure of the third angle, angle CC.
Angle C=180(40+70)=70C = 180^\circ - (40^\circ + 70^\circ) = 70^\circ.
The sum of interior angles in any triangle is 180180^\circ.
2
Determine the relationship between the side lengths using the angle measures.
Side AC=AB=8AC = AB = 8 centimeters.
Since angle B=70B = 70^\circ and angle C=70C = 70^\circ, triangle ABCABC is isosceles. Sides opposite equal angles are equal in length, so the side opposite angle CC (which is ABAB) equals the side opposite angle BB (which is ACAC).
3
Use the perimeter formula to find the length of side BCBC.
Length of side BC=22(8+8)=6BC = 22 - (8 + 8) = 6 centimeters.
Perimeter is the total boundary distance (AB+AC+BC=22AB + AC + BC = 22). Substituting known values gives 8+8+BC=228 + 8 + BC = 22, so BC=6BC = 6.

Anahtar Kavram

Isosceles Triangle Side-Angle Properties and Perimeter
Tahmini Süre:45s
Soru 1426Soru

Dataset AA consists of nn numerical values with a standard deviation of σA\sigma_A and an interquartile range of IQRA\text{IQR}_A. Dataset BB is constructed by multiplying each value in Dataset AA by 44 and then subtracting 1010 from each resulting value. Which of the following correctly expresses the standard deviation σB\sigma_B and the interquartile range IQRB\text{IQR}_B of Dataset BB in terms of σA\sigma_A and IQRA\text{IQR}_A?

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Cevap: σB=4σA\sigma_B = 4\sigma_A and IQRB=4IQRA\text{IQR}_B = 4\text{IQR}_A

Cevap

σB=4σA\sigma_B = 4\sigma_A and IQRB=4IQRA\text{IQR}_B = 4\text{IQR}_A
When a dataset undergoes a linear transformation of the form Y=cX+kY = cX + k, any measure of dispersion DD (such as standard deviation or interquartile range) transforms according to DY=cDXD_Y = |c| \cdot D_X. The constant shift kk shifts all points equally and does not affect spread. Therefore, multiplying by 44 multiplies both σA\sigma_A and IQRA\text{IQR}_A by 44, and subtracting 1010 has no effect on either measure.

Adım Adım Çözüm

1
Analyze the effect of multiplying each value in a dataset by a positive constant c=4c = 4.
Multiplying all data values by cc scales all measures of spread (including standard deviation, range, and interquartile range) by c=4|c| = 4. Thus, initial scaled values give 4σA4\sigma_A and 4IQRA4\text{IQR}_A.
Measures of dispersion reflect distances between data points, which scale linearly when all values are multiplied by a constant.
2
Analyze the effect of subtracting a constant k=10k = 10 from each data point.
Subtracting a constant shifts the entire distribution along the number line without altering the relative distances between any data points.
Because measures of dispersion measure relative spread rather than absolute location, adding or subtracting a constant has zero effect on standard deviation or interquartile range.
3
Combine the transformation effects to state σB\sigma_B and IQRB\text{IQR}_B.
σB=4σA\sigma_B = 4\sigma_A and IQRB=4IQRA\text{IQR}_B = 4\text{IQR}_A.
The multiplicative factor scales both metrics by 4, and the additive shift of 10-10 leaves both metrics unchanged.

Anahtar Kavram

Linear Transformations on Measures of Dispersion
Tahmini Süre:1m 15s
Soru 1427Soru

Lines L1L_1 and L2L_2 intersect at point PP to form an acute angle of 5454^\circ. Line MM passes through point PP and is perpendicular to line L1L_1. Ray RR originates at point PP and lies in the interior of one of the obtuse angles formed by L1L_1 and L2L_2. If Ray RR bisects the angle formed between line MM and line L2L_2, what is the measure, in degrees, of the acute angle formed by Ray RR and line L1L_1?

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Cevap: 72

Cevap

The measure of the acute angle formed by Ray RR and line L1L_1 is 7272^\circ.
Lines L1L_1 and L2L_2 form an obtuse angle of 18054=126180^\circ - 54^\circ = 126^\circ. Perpendicular line MM consumes 9090^\circ of this angle relative to L1L_1, leaving 3636^\circ between line MM and line L2L_2. Bisecting this remaining angle gives 1818^\circ. Ray RR therefore lies 1818^\circ away from perpendicular line MM, making an acute angle of 9018=7290^\circ - 18^\circ = 72^\circ with line L1L_1.

Adım Adım Çözüm

1
Determine the measure of the obtuse angle between lines L1L_1 and L2L_2.
The obtuse angle measures 18054=126180^\circ - 54^\circ = 126^\circ.
Adjacent angles along intersecting straight lines are supplementary and sum to 180180^\circ.
2
Find the angle between perpendicular line MM and line L2L_2.
The angle between line MM and line L2L_2 within the obtuse region is 12690=36126^\circ - 90^\circ = 36^\circ.
Line MM is perpendicular to line L1L_1, taking up 9090^\circ of the 126126^\circ obtuse angle.
3
Determine the angle formed by Ray RR after bisecting the 3636^\circ angle.
The angle between Ray RR and line MM is 36/2=1836^\circ / 2 = 18^\circ.
An angle bisector divides an angle into two equal parts.
4
Calculate the acute angle between Ray RR and line L1L_1.
The acute angle formed between Ray RR and line L1L_1 is 9018=7290^\circ - 18^\circ = 72^\circ.
Line MM forms a 9090^\circ angle with line L1L_1. Subtracting the 1818^\circ offset created by Ray RR yields the acute angle of 7272^\circ.

Anahtar Kavram

Supplementary angles, perpendicular lines, and angle bisectors
Tahmini Süre:2m 0s
Soru 1428Soru

If xx is a real number that satisfies both 43x>7|4 - 3x| > 7 and 12x33\frac{1 - 2x}{3} \ge -3, which of the following represents the complete set of all possible values of xx?

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Cevap: x<1x < -1 or 113<x5\frac{11}{3} < x \le 5

Cevap

x<1x < -1 or 113<x5\frac{11}{3} < x \le 5
The correct option correctly solves 43x>7|4 - 3x| > 7 to yield x<1x < -1 or x>113x > \frac{11}{3}, solves 12x33\frac{1 - 2x}{3} \ge -3 to yield x5x \le 5, and takes their intersection to produce x<1x < -1 or 113<x5\frac{11}{3} < x \le 5.

Adım Adım Çözüm

1
Solve the absolute value inequality 43x>7|4 - 3x| > 7.
43x>74 - 3x > 7 or 43x<74 - 3x < -7. Solving 43x>74 - 3x > 7 gives 3x>3    x<1-3x > 3 \implies x < -1. Solving 43x<74 - 3x < -7 gives 3x<11    x>113-3x < -11 \implies x > \frac{11}{3}. Thus, x(,1)(113,)x \in (-\infty, -1) \cup (\frac{11}{3}, \infty).
An absolute value inequality of the form u>c|u| > c splits into u>cu > c or u<cu < -c. Dividing by a negative number reverses the inequality direction.
2
Solve the linear inequality 12x33\frac{1 - 2x}{3} \ge -3.
Multiply both sides by 33: 12x91 - 2x \ge -9. Subtract 11: 2x10-2x \ge -10. Divide by 2-2 and flip the inequality sign: x5x \le 5.
Isolating the variable xx requires reversing the inequality sign when dividing by the negative constant 2-2.
3
Find the intersection of the solution sets from Step 1 and Step 2.
We require xx to satisfy (x<1 or x>113)(x < -1 \text{ or } x > \frac{11}{3}) AND x5x \le 5. Case 1: x<1x < -1 automatically satisfies x5x \le 5, giving x<1x < -1. Case 2: x>113x > \frac{11}{3} combined with x5x \le 5 gives 113<x5\frac{11}{3} < x \le 5. Combining both cases yields x<1 or 113<x5x < -1 \text{ or } \frac{11}{3} < x \le 5.
The word 'both' in the stem indicates a logical AND (intersection) between the two conditions.

Anahtar Kavram

Solving systems involving absolute value inequalities and linear inequalities requires handling disjunctions (OR) for absolute values greater than a positive constant, reversing inequality signs when multiplying or dividing by negative numbers, and taking the intersection (AND) of all valid regions.
Tahmini Süre:2m 15s
Soru 1429Soru

A right circular cylinder has a base radius of 33 units and a height of 44 units. Which of the following statements regarding this cylinder are true? Select all such statements.

Geçerli olan tümünü seçin

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Cevap: The volume of the cylinder is 36π36\pi cubic units.; The total surface area of the cylinder is 42π42\pi square units.

Cevap

The correct statements are that the volume of the cylinder is 36π36\pi cubic units and the total surface area of the cylinder is 42π42\pi square units.
The volume of a cylinder with radius 33 and height 44 is V=πr2h=π(3)2(4)=36πV = \pi r^2 h = \pi(3)^2(4) = 36\pi. The total surface area is A=2πrh+2πr2=2π(3)(4)+2π(3)2=24π+18π=42πA = 2\pi r h + 2\pi r^2 = 2\pi(3)(4) + 2\pi(3)^2 = 24\pi + 18\pi = 42\pi. Therefore, both statements asserting these exact values are correct.

Adım Adım Çözüm

1
Calculate the volume of the right circular cylinder
Volume V=πr2h=π(32)(4)=36πV = \pi r^2 h = \pi (3^2)(4) = 36\pi
The formula for the volume of a right circular cylinder is V=πr2hV = \pi r^2 h.
2
Calculate the lateral surface area and total surface area of the cylinder
Lateral Area = 2πrh=24π2\pi r h = 24\pi; Total Area = 24π+2(π32)=42π24\pi + 2(\pi \cdot 3^2) = 42\pi
Total surface area is the sum of the lateral surface area (2πrh2\pi r h) and the areas of the two circular bases (2πr22\pi r^2).
3
Evaluate the base-to-lateral surface area ratio
Ratio = 9π24π=38\frac{9\pi}{24\pi} = \frac{3}{8}
Comparing the base area (9π9\pi) to the lateral area (24π24\pi) simplifies to 3:83:8.

Anahtar Kavram

Volume and surface area formulas for right circular cylinders
Soru 1430Soru

If xx is a real number that satisfies the inequality 23x4+57-2|3x - 4| + 5 \ge -7, which of the following inequalities represents all possible values of xx?

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Cevap: 23x103-\frac{2}{3} \le x \le \frac{10}{3}

Cevap

23x103-\frac{2}{3} \le x \le \frac{10}{3}
Isolating 3x4|3x - 4| requires dividing 23x412-2|3x - 4| \ge -12 by 2-2, which reverses the inequality to 3x46|3x - 4| \le 6. Expanding this into the compound inequality 63x46-6 \le 3x - 4 \le 6 and solving for xx yields the interval 23x103-\frac{2}{3} \le x \le \frac{10}{3}.

Adım Adım Çözüm

1
Isolate the absolute value expression by subtracting 5 from both sides of the inequality.
23x412-2|3x - 4| \ge -12
Before removing absolute value bars, the term 3x4|3x - 4| must be isolated on one side.
2
Divide both sides by 2-2 and reverse the inequality sign.
3x46|3x - 4| \le 6
Dividing an inequality by a negative number reverses the direction of the inequality sign.
3
Express the absolute value inequality uk|u| \le k as a double inequality kuk-k \le u \le k.
63x46-6 \le 3x - 4 \le 6
The distance of 3x43x - 4 from 0 on the number line must be at most 6 units.
4
Add 4 to all three parts of the inequality and divide by 3.
23x10    23x103-2 \le 3x \le 10 \implies -\frac{2}{3} \le x \le \frac{10}{3}
Solving for xx isolates the variable in the center of the double inequality.

Anahtar Kavram

Solving linear absolute value inequalities requires reversing the inequality sign when multiplying or dividing by negative numbers, and expressing AB|A| \le B as BAB-B \le A \le B.
Soru 1431Soru

In the geometric plane, line kk is parallel to line mm (kmk \parallel m). Transversal line tt intersects line kk at point AA and line mm at point BB. Point CC lies on line kk to the left of AA, such that interior acute angle CAB=(3x10)\angle CAB = (3x - 10)^\circ. Ray ADAD bisects CAB\angle CAB. Ray BFBF is drawn into the region between lines kk and mm making an angle ABF=(x+35)\angle ABF = (x + 35)^\circ with transversal segment ABAB. Ray ADAD and ray BFBF intersect at point PP inside the parallel region. Line PBPB is extended past PP to intersect line kk at point QQ. If ray ADAD is perpendicular to ray BFBF, what is the measure of the obtuse angle formed at the intersection of line QBQB and line kk?

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Cevap: 121121^\circ

Cevap

The measure of the obtuse angle formed at the intersection of line QBQB and line kk is 121121^\circ.
The measure 121121^\circ is correct because ray ADAD bisects CAB\angle CAB, giving PAB=(1.5x5)\angle PAB = (1.5x - 5)^\circ. Since ADBFAD \perp BF, APB\triangle APB is a right triangle where (1.5x5)+(x+35)=90(1.5x - 5) + (x + 35) = 90, yielding x=24x = 24. Consequently, QAB=62\angle QAB = 62^\circ and ABQ=59\angle ABQ = 59^\circ. In ABQ\triangle ABQ, the acute angle AQB=180(62+59)=59\angle AQB = 180^\circ - (62^\circ + 59^\circ) = 59^\circ. The supplementary obtuse angle along line kk is 18059=121180^\circ - 59^\circ = 121^\circ.

Adım Adım Çözüm

1
Express the angle PAB\angle PAB in terms of xx.
Since ray ADAD bisects CAB=(3x10)\angle CAB = (3x - 10)^\circ, PAB=3x102=(1.5x5)\angle PAB = \frac{3x - 10}{2} = (1.5x - 5)^\circ.
An angle bisector divides an angle into two equal halves.
2
Set up an equation using triangle APB\triangle APB.
In APB\triangle APB, APB=90\angle APB = 90^\circ because ray ADAD \perp ray BFBF. Therefore, PAB+ABP=90    (1.5x5)+(x+35)=90    2.5x+30=90    2.5x=60    x=24\angle PAB + \angle ABP = 90^\circ \implies (1.5x - 5) + (x + 35) = 90 \implies 2.5x + 30 = 90 \implies 2.5x = 60 \implies x = 24.
The acute angles in a right triangle sum to 9090^\circ.
3
Calculate the measures of CAB\angle CAB and ABQ\angle ABQ.
CAB=3(24)10=62\angle CAB = 3(24) - 10 = 62^\circ, and ABQ=ABF=24+35=59\angle ABQ = \angle ABF = 24 + 35 = 59^\circ.
Substitute x=24x = 24 back into the original angle expressions.
4
Determine the acute angle AQB\angle AQB in triangle ABQ\triangle ABQ.
In ABQ\triangle ABQ, points Q,C,AQ, C, A lie on line kk, so QAB=CAB=62\angle QAB = \angle CAB = 62^\circ. Sum of angles in ABQ\triangle ABQ: AQB=180(62+59)=180121=59\angle AQB = 180^\circ - (62^\circ + 59^\circ) = 180^\circ - 121^\circ = 59^\circ.
The interior angles of any triangle sum to 180180^\circ.
5
Find the supplementary obtuse angle at intersection point QQ.
Obtuse angle =18059=121= 180^\circ - 59^\circ = 121^\circ.
Angles forming a linear pair on a straight line are supplementary.

Anahtar Kavram

Parallel Lines, Transversals, Angle Bisectors, and Triangle Angle Sum Theorem
Soru 1432Soru

If x3<5|x - 3| < 5, which of the following values could be the value of xx? Select all such values.

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Cevap: 1-1; 00; 44

Cevap

The possible values of xx are 1-1, 00, and 44.
The absolute value inequality x3<5|x - 3| < 5 represents all real numbers xx whose distance from 33 on the number line is strictly less than 55. Expressed as a compound inequality, this means 5<x3<5-5 < x - 3 < 5. Adding 33 across the entire inequality yields 2<x<8-2 < x < 8. The values 1-1, 00, and 44 are the only options that fall strictly within the interval (2,8)(-2, 8).

Adım Adım Çözüm

1
Rewrite the absolute value inequality as a compound inequality.
5<x3<5-5 < x - 3 < 5
An absolute value inequality of the form u<k|u| < k (where k>0k > 0) is equivalent to k<u<k-k < u < k.
2
Solve for xx by adding 33 to all parts of the inequality.
5+3<x<5+3    2<x<8-5 + 3 < x < 5 + 3 \implies -2 < x < 8
Adding a positive constant to all parts of an inequality isolates xx while preserving inequality directions.
3
Test each given option against the range 2<x<8-2 < x < 8.
The values 1-1, 00, and 44 lie within (2,8)(-2, 8), whereas 3-3 and 88 lie outside.
3-3 is less than or equal to 2-2, and 88 is not strictly less than 88.

Anahtar Kavram

Solving linear absolute value inequalities
Tahmini Süre:45s
Soru 1433Soru
If xx satisfies the linear equation
3(x2)4x53=2x+16+2\frac{3(x - 2)}{4} - \frac{x - 5}{3} = \frac{2x + 1}{6} + 2
what is the value of 2x52x - 5?
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Cevap: 43

Cevap

43
The correct answer is obtained by clearing denominators with the least common denominator 12, yielding 9(x2)4(x5)=2(2x+1)+249(x - 2) - 4(x - 5) = 2(2x + 1) + 24. Expanding and simplifying gives 5x+2=4x+265x + 2 = 4x + 26, which isolates x=24x = 24. Substituting x=24x = 24 into 2x52x - 5 results in 2(24)5=432(24) - 5 = 43.

Adım Adım Çözüm

1
Clear the denominators by multiplying every term in the equation by the least common multiple of 4, 3, and 6, which is 12.
123(x2)412x53=122x+16+122    9(x2)4(x5)=2(2x+1)+2412 \cdot \frac{3(x - 2)}{4} - 12 \cdot \frac{x - 5}{3} = 12 \cdot \frac{2x + 1}{6} + 12 \cdot 2 \implies 9(x - 2) - 4(x - 5) = 2(2x + 1) + 24
Eliminating fractions simplifies the linear equation into standard polynomial form.
2
Distribute the constants through the parentheses, taking careful note of negative signs.
9x184x+20=4x+2+249x - 18 - 4x + 20 = 4x + 2 + 24
Parentheses must be removed to collect like variable and constant terms.
3
Combine like terms on both sides of the equation.
5x+2=4x+265x + 2 = 4x + 26
Consolidating terms on each side allows for isolating the variable.
4
Isolate xx on one side of the equation.
5x4x=262    x=245x - 4x = 26 - 2 \implies x = 24
Subtracting 4x4x and 2 from both sides solves directly for xx.
5
Evaluate the target expression 2x52x - 5 using x=24x = 24.
2(24)5=485=432(24) - 5 = 48 - 5 = 43
The question requests the value of 2x52x - 5, not xx alone.

Anahtar Kavram

Solving multi-step linear equations in one variable with fractional terms and evaluating algebraic expressions.
Tahmini Süre:2m 0s
Soru 1434Soru

A square is inscribed in a circle with center OO. The perimeter of the square is 16216\sqrt{2} units. A sector of this circle has an area equal to the total area of the region inside the circle that lies outside the square. What is the arc length of this sector?

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Cevap: 8π168\pi - 16

Cevap

8π168\pi - 16
The correct answer is 8π168\pi - 16. The inscribed square has side length 424\sqrt{2} and diagonal 88. Since the diagonal of an inscribed square is the circle's diameter, the circle has radius r=4r = 4 and total area 16π16\pi. The square has area 3232, so the region outside the square has area 16π3216\pi - 32. For any sector of radius rr, the arc length LL and sector area AA satisfy L=2ArL = \frac{2A}{r}. Substituting A=16π32A = 16\pi - 32 and r=4r = 4 yields L=2(16π32)4=8π16L = \frac{2(16\pi - 32)}{4} = 8\pi - 16.

Adım Adım Çözüm

1
Find the side length and diagonal of the inscribed square.
Side length s=1624=42s = \frac{16\sqrt{2}}{4} = 4\sqrt{2}. Diagonal d=s2=(42)2=8d = s\sqrt{2} = (4\sqrt{2})\sqrt{2} = 8.
The perimeter of a square is 4s4s, and the diagonal of a square with side ss is s2s\sqrt{2}.
2
Determine the radius and total area of the circle.
Diameter equals diagonal d=8d = 8, so radius r=4r = 4. Area of circle Acircle=πr2=16πA_{\text{circle}} = \pi r^2 = 16\pi.
A square inscribed in a circle has its diagonal aligned with the diameter of the circle.
3
Calculate the area of the region inside the circle but outside the square.
Area of square Asquare=(42)2=32A_{\text{square}} = (4\sqrt{2})^2 = 32. Area outside square Aoutside=16π32A_{\text{outside}} = 16\pi - 32.
Subtract the area of the inscribed square from the total area of the circle.
4
Relate sector area to arc length using L=2AsectorrL = \frac{2 A_{\text{sector}}}{r}.
L=2(16π32)4=32π644=8π16L = \frac{2(16\pi - 32)}{4} = \frac{32\pi - 64}{4} = 8\pi - 16.
Since sector area Asector=θ360πr2A_{\text{sector}} = \frac{\theta}{360^\circ}\pi r^2 and arc length L=θ360(2πr)L = \frac{\theta}{360^\circ}(2\pi r), we have L=2AsectorrL = \frac{2A_{\text{sector}}}{r}.

Anahtar Kavram

Relationship between circle area, inscribed figures, sector area, and arc length
Tahmini Süre:1m 30s
Soru 1435Soru

Working alone at a constant rate, Pump A can drain a full water reservoir in 66 hours, while Pump B working alone at a constant rate can drain the same full reservoir in 44 hours. Which of the following statements must be true? Select all such statements.

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Cevap: Working together, Pump A and Pump B can drain the entire reservoir in 2.42.4 hours.; In 11 hour, Pump A and Pump B working together drain 512\frac{5}{12} of the total reservoir volume.

Cevap

The statements confirming that the two pumps together drain the reservoir in 2.4 hours and that they drain 5/12 of the reservoir in 1 hour are correct.
The rate for Pump A is 16\frac{1}{6} job/hr and for Pump B is 14\frac{1}{4} job/hr. Their combined rate is 16+14=512\frac{1}{6} + \frac{1}{4} = \frac{5}{12} of the reservoir per hour, which directly validates the statement regarding 1 hour of combined work. Dividing 11 full reservoir by 512\frac{5}{12} yields 2.42.4 hours, which validates the total elapsed time statement.

Adım Adım Çözüm

1
Calculate individual work rates
Pump A rate = 16\frac{1}{6} reservoir/hr, Pump B rate = 14\frac{1}{4} reservoir/hr
Work rate is the reciprocal of time required to complete the job.
2
Calculate combined work rate
Combined rate = 16+14=212+312=512\frac{1}{6} + \frac{1}{4} = \frac{2}{12} + \frac{3}{12} = \frac{5}{12} reservoir/hr
Rates add when workers/pumps perform simultaneously.
3
Calculate time needed for full task
Total time = 1Combined Rate=125=2.4\frac{1}{\text{Combined Rate}} = \frac{12}{5} = 2.4 hours
Total work (11) divided by combined rate gives total elapsed time.

Anahtar Kavram

Combined Work Rates and Inverse Time Relationships
Tahmini Süre:1m 0s
Soru 1436Soru

Four rays, OA\vec{OA}, OB\vec{OB}, OC\vec{OC}, and OD\vec{OD}, radiate from a common point OO in consecutive clockwise order such that OAOC\vec{OA} \perp \vec{OC} and OBOD\vec{OB} \perp \vec{OD}. If the measure of angle AOD\angle AOD is 3.53.5 times the measure of angle BOC\angle BOC, what is the measure, in degrees, of angle AOB\angle AOB?

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Cevap: 5050^\circ

Cevap

5050^\circ
Because OAOC\vec{OA} \perp \vec{OC} and OBOD\vec{OB} \perp \vec{OD}, we know AOB+BOC=90\angle AOB + \angle BOC = 90^\circ and BOC+COD=90\angle BOC + \angle COD = 90^\circ, which implies AOB=COD\angle AOB = \angle COD. The total angle AOD=AOB+BOD=AOB+90\angle AOD = \angle AOB + \angle BOD = \angle AOB + 90^\circ. Using the given condition AOD=3.5×BOC\angle AOD = 3.5 \times \angle BOC, we substitute BOC=90AOB\angle BOC = 90^\circ - \angle AOB to get AOB+90=3.5(90AOB)\angle AOB + 90^\circ = 3.5(90^\circ - \angle AOB), which solves to AOB=50\angle AOB = 50^\circ.

Adım Adım Çözüm

1
Set up angle variable definitions and perpendicular relationships.
Let AOB=x\angle AOB = x, BOC=y\angle BOC = y, and COD=z\angle COD = z. Since OAOC\vec{OA} \perp \vec{OC}, we have x+y=90x + y = 90^\circ. Since OBOD\vec{OB} \perp \vec{OD}, we have y+z=90y + z = 90^\circ.
Perpendicular rays form right angles measuring 9090^\circ.
2
Deduce the relationship between xx, yy, and zz, and express AOD\angle AOD in terms of xx.
Subtracting yy from both equations gives x=90yx = 90^\circ - y and z=90yz = 90^\circ - y, so x=zx = z. Thus, AOD=x+y+z=x+90\angle AOD = x + y + z = x + 90^\circ.
Adjacent angles sharing a vertex add up to form the overall combined angle.
3
Formulate and solve the equation based on the given ratio.
We are given AOD=3.5×BOC\angle AOD = 3.5 \times \angle BOC, so x+90=3.5yx + 90^\circ = 3.5y. Substituting y=90xy = 90^\circ - x yields x+90=3.5(90x)    x+90=3153.5x    4.5x=225    x=50x + 90^\circ = 3.5(90^\circ - x) \implies x + 90^\circ = 315^\circ - 3.5x \implies 4.5x = 225^\circ \implies x = 50^\circ.
Substitution creates a single linear equation in terms of x=AOBx = \angle AOB.

Anahtar Kavram

Perpendicular Ray Systems and Angle Addition
Tahmini Süre:1m 30s
Soru 1437Soru

Let PP be the product of all positive real numbers xx that satisfy the exponential equation xx=(x2x)xx^{\sqrt{x}} = \left(x^2\sqrt{x}\right)^x. What is the value of PP?

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Cevap: 425\frac{4}{25}

Cevap

425\frac{4}{25}
Simplifying the right-hand side yields xx=x52xx^{\sqrt{x}} = x^{\frac{5}{2}x}. For x=1x = 1, both sides equal 1, making x=1x = 1 a valid solution. For x>0x > 0 and x1x \neq 1, equating the exponents gives x=52x\sqrt{x} = \frac{5}{2}x, which reduces to x=25\sqrt{x} = \frac{2}{5}, so x=425x = \frac{4}{25}. Multiplying all valid solutions together yields 1425=4251 \cdot \frac{4}{25} = \frac{4}{25}.

Adım Adım Çözüm

1
Simplify the right-hand side of the equation using fractional exponent rules.
Since x2x=x2x1/2=x5/2x^2\sqrt{x} = x^2 \cdot x^{1/2} = x^{5/2}, the equation becomes xx=(x5/2)x=x52xx^{\sqrt{x}} = \left(x^{5/2}\right)^x = x^{\frac{5}{2}x}.
Combining terms with the same base into a single exponent simplifies comparison between both sides.
2
Check for the base root x=1x = 1.
Substituting x=1x = 1 gives 11=11=11^{\sqrt{1}} = 1^1 = 1 and (121)1=11=1(1^2\sqrt{1})^1 = 1^1 = 1. Thus, x=1x = 1 is a valid solution.
For any exponential equation of the form xf(x)=xg(x)x^{f(x)} = x^{g(x)}, x=1x = 1 is always a candidate solution because 1a=1b=11^a = 1^b = 1 for all real exponents.
3
Equate the exponents for positive real solutions where x1x \neq 1.
Setting the exponents equal gives x=52x\sqrt{x} = \frac{5}{2}x.
When the base x>0x > 0 and x1x \neq 1, xf(x)=xg(x)x^{f(x)} = x^{g(x)} implies f(x)=g(x)f(x) = g(x).
4
Solve the resulting radical equation for xx.
Divide both sides by x\sqrt{x} (since x>0x > 0): 1=52x    x=25    x=(25)2=4251 = \frac{5}{2}\sqrt{x} \implies \sqrt{x} = \frac{2}{5} \implies x = \left(\frac{2}{5}\right)^2 = \frac{4}{25}.
Isolating x\sqrt{x} and squaring both sides gives the non-trivial solution.
5
Compute the product PP of all positive real solutions.
P=1425=425P = 1 \cdot \frac{4}{25} = \frac{4}{25}.
The question requests the product of all positive real values of xx satisfying the original equation.

Anahtar Kavram

Solving exponential equations with variable bases and radical powers
Soru 1438Soru

A research team measured the height, in centimeters, of 15 plants in a greenhouse. The dataset has a range of 24 cm24\text{ cm}, an interquartile range (IQR) of 10 cm10\text{ cm}, and a standard deviation of 5.2 cm5.2\text{ cm}. If the height of every plant is increased by exactly 8 cm8\text{ cm}, which of the following statements regarding the modified dataset must be true? Select all such statements.

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Cevap: The range of the modified dataset is 24 cm24\text{ cm}.; The standard deviation of the modified dataset is 5.2 cm5.2\text{ cm}.

Cevap

The statement that the range of the modified dataset is 24 cm24\text{ cm} and the statement that the standard deviation of the modified dataset is 5.2 cm5.2\text{ cm} are both true.
When a constant is added to every value in a dataset, the entire distribution shifts by that amount. Consequently, the relative positions and distances between data points do not change, leaving measures of dispersion (range, IQR, standard deviation) unchanged. Therefore, the range remains 24 cm24\text{ cm} and the standard deviation remains 5.2 cm5.2\text{ cm}.

Adım Adım Çözüm

1
Analyze the effect of adding a constant to a dataset on measures of dispersion.
Adding a constant kk to every data value shifts the center (mean, median) by kk, but all measures of spread (range, IQR, standard deviation) remain completely unchanged.
Measures of dispersion quantify the spread or distance between data values, which is invariant under a uniform translation.
2
Evaluate each statement against the unchanged measures of dispersion.
The range remains 24 cm24\text{ cm}, the IQR remains 10 cm10\text{ cm}, and the standard deviation remains 5.2 cm5.2\text{ cm}.
Comparing the calculated original measures to the statements shows that the range of 24 cm24\text{ cm} and standard deviation of 5.2 cm5.2\text{ cm} are correct.

Anahtar Kavram

Effect of Linear Transformations (Addition of a Constant) on Measures of Dispersion
Soru 1439Soru

In circle OO, minor arc ABAB is subtended by a central angle of 120120^\circ, and the radius of circle OO is 66. A smaller circle, circle CC, is constructed such that it is tangent to chord ABAB at its midpoint and tangent to minor arc ABAB at its midpoint. What is the area of a sector of circle CC subtended by a central angle of 9090^\circ?

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Cevap: 9π16\frac{9\pi}{16}

Cevap

9π16\frac{9\pi}{16}
The distance from the center of circle OO to chord ABAB is 6cos(60)=36 \cos(60^\circ) = 3, leaving a height of 63=36 - 3 = 3 for the minor segment. Circle CC is tangent to the chord and arc midpoints, making its diameter equal to 33 and its radius 32\frac{3}{2}. The area of a 9090^\circ sector of circle CC is 90360π(32)2=9π16\frac{90^\circ}{360^\circ} \pi \left(\frac{3}{2}\right)^2 = \frac{9\pi}{16}.

Adım Adım Çözüm

1
Find the perpendicular distance from center OO to chord ABAB.
In isosceles triangle OABOAB with OA=OB=6OA = OB = 6 and central angle AOB=120\angle AOB = 120^\circ, the perpendicular bisector from OO to ABAB meets ABAB at midpoint MM. AOM=60\angle AOM = 60^\circ, so OM=OAcos(60)=6×12=3OM = OA \cos(60^\circ) = 6 \times \frac{1}{2} = 3.
Determining OMOM allows us to find the sagitta (height) of the minor segment bounded by chord ABAB and minor arc ABAB.
2
Calculate the height of the minor segment (diameter of circle CC).
The height of the minor segment along the radius passing through MM to arc midpoint NN is MN=ONOM=63=3MN = ON - OM = 6 - 3 = 3. Since circle CC is tangent to ABAB at MM and to the arc at NN, segment MNMN is a diameter of circle CC, giving a diameter of 33.
The space between the chord midpoint and arc midpoint bounds circle CC, defining its diameter.
3
Find the radius of circle CC.
Radius rC=diameter2=32r_C = \frac{\text{diameter}}{2} = \frac{3}{2}.
The radius of circle CC is needed to calculate its sector area.
4
Compute the area of the 9090^\circ sector of circle CC.
\text{Area} = \frac{\theta}{360^\circ} \pi r_C^2 = \frac{90^\circ}{360^\circ} \pi \left(\frac{3}{2}\right)^2 = \frac{1}{4} \pi \left(\frac{9}{4}\right) = \frac{9\pi}{16}.
Multiply the fraction of the full circle represented by the central angle by the total area of circle CC.

Anahtar Kavram

Calculating sector area of an inscribed circle within a circle segment
Tahmini Süre:2m 0s
Soru 1440Soru

Dataset SS consists of 10 distinct numerical values. Dataset TT is created by replacing the maximum value of Dataset SS with a number that is strictly greater than that maximum value, while all other 9 values remain unchanged. Which of the following statements comparing Dataset SS and Dataset TT must be true? Select all that apply.

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Cevap: The range of Dataset TT is greater than the range of Dataset SS.; The interquartile range (IQR) of Dataset TT is equal to the interquartile range of Dataset SS.

Cevap

The statements asserting that the range of Dataset TT is greater than the range of Dataset SS and that the interquartile range (IQR) of Dataset TT is equal to the interquartile range of Dataset SS are correct.
The statement regarding the range is correct because increasing the maximum value increases the difference between the maximum and minimum values. The statement regarding the interquartile range is correct because the 25th percentile (Q1Q_1) and 75th percentile (Q3Q_3) depend only on the first 8 ordered elements of a 10-element dataset, so changing the 10th element leaves Q1Q_1 and Q3Q_3 identical.

Adım Adım Çözüm

1
Analyze the impact on Range
Range(T)>Range(S)\text{Range}(T) > \text{Range}(S)
Range is defined as MaximumMinimum\text{Maximum} - \text{Minimum}. Since the minimum is unchanged and the maximum increases, the range must increase.
2
Analyze the impact on Interquartile Range (IQR)
IQR(T)=IQR(S)\text{IQR}(T) = \text{IQR}(S)
IQR is Q3Q1Q_3 - Q_1. For 10 ordered elements, Q1Q_1 and Q3Q_3 depend on the positions of the bottom 75% of the data. Modifying only the 10th (largest) element leaves Q1Q_1 and Q3Q_3 unchanged.
3
Analyze the impact on Median and Standard Deviation
Median is unchanged; Standard deviation increases.
The median depends on the 5th and 6th values, which are unaffected. Moving an extreme value further out increases distance from the mean, strictly increasing standard deviation.

Anahtar Kavram

Effect of outlier modification on measures of position (Q1,Q3Q_1, Q_3, Median) versus measures of dispersion (Range, Standard Deviation, IQR).
ÖncekiSayfa 72 / 107Sonraki
Tüm alıştırma soruları — GRE General Test | Examkin