Tüm alıştırma soruları

2131 soru

Soru 1401Soru

In the geometric plane, line kk is parallel to line mm. A transversal line tt intersects line kk at point PP and line mm at point QQ. Ray PRPR extends along line kk to the right of PP, and ray QSQS extends along line mm to the right of QQ. The measure of interior angle RPQ\angle RPQ is represented by (3x+20)(3x + 20)^\circ and the measure of interior angle PQS\angle PQS is represented by (2x+10)(2x + 10)^\circ. Which of the following statements must be true? Select all such statements.

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Cevap: The value of xx is 3030.; The measure of angle RPQ\angle RPQ is 110110^\circ.; The acute angle formed by line tt and line kk at point PP measures 7070^\circ.

Cevap

The true statements are that x=30x = 30, the measure of angle RPQ\angle RPQ is 110110^\circ, and the acute angle formed by line tt and line kk at point PP measures 7070^\circ.
Lines kk and mm are parallel, so interior angles on the same side of transversal tt (angles RPQ\angle RPQ and PQS\angle PQS) are supplementary. Solving (3x+20)+(2x+10)=180(3x + 20) + (2x + 10) = 180 gives x=30x = 30. Substituting x=30x = 30 yields RPQ=110\angle RPQ = 110^\circ and PQS=70\angle PQS = 70^\circ. The adjacent angle to RPQ\angle RPQ at point PP is 180110=70180^\circ - 110^\circ = 70^\circ, which is acute.

Adım Adım Çözüm

1
Set up the geometric equation using the parallel line angle relationship.
(3x+20)+(2x+10)=180(3x + 20) + (2x + 10) = 180
When two parallel lines are cut by a transversal, consecutive interior angles on the same side of the transversal are supplementary (their sum is 180180^\circ).
2
Solve the linear equation for xx.
5x+30=180    5x=150    x=305x + 30 = 180 \implies 5x = 150 \implies x = 30
Combine like terms and isolate xx using basic algebra.
3
Calculate the specific angle measures.
m RPQ=3(30)+20=110\angle RPQ = 3(30) + 20 = 110^\circ and m PQS=2(30)+10=70\angle PQS = 2(30) + 10 = 70^\circ
Substitute x=30x = 30 into the given algebraic angle expressions.
4
Determine the supplementary acute angle at point PP.
180110=70180^\circ - 110^\circ = 70^\circ
Angles along a straight line form a linear pair and sum to 180180^\circ.

Anahtar Kavram

Parallel Lines and Consecutive Interior Angles
Soru 1402Soru

Circle KK has a radius of 1010. Points PP and QQ lie on circle KK such that central angle POQ\angle POQ measures 7272^\circ, where point OO is the center of circle KK. Which of the following statements are true? Select all that apply.

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Cevap: The length of minor arc PQPQ is 4π4\pi.; The area of sector POQPOQ is 20π20\pi.

Cevap

The correct statements are that the length of minor arc PQPQ is 4π4\pi, and the area of sector POQPOQ is 20π20\pi.
The central angle of 7272^\circ corresponds to 72360=15\frac{72^\circ}{360^\circ} = \frac{1}{5} of the entire circle. The circle has a circumference of 2π(10)=20π2\pi(10) = 20\pi and an area of π(10)2=100π\pi(10)^2 = 100\pi. Taking 15\frac{1}{5} of the circumference gives an arc length of 4π4\pi, and taking 15\frac{1}{5} of the total area gives a sector area of 20π20\pi. Both of these statements are mathematically accurate.

Adım Adım Çözüm

1
Find the central angle fraction relative to the full circle
Fraction=72360=15\text{Fraction} = \frac{72^\circ}{360^\circ} = \frac{1}{5}
A complete circle subtends 360360^\circ, so the arc and sector comprise one-fifth of the circle.
2
Calculate the circumference and length of minor arc PQPQ
\text{Circumference} = 2\pi(10) = 20\pi, \quad \text{Arc Length } PQ = \frac{1}{5} \times 20\pi = 4\pi
Arc length is the central angle fraction multiplied by the total circumference.
3
Calculate the total circle area and area of sector POQPOQ
\text{Total Area} = \pi(10)^2 = 100\pi, \quad \text{Sector Area } POQ = \frac{1}{5} \times 100\pi = 20\pi
Sector area is the central angle fraction multiplied by the total area of the circle.
4
Evaluate sector perimeter and area ratio for remaining options
\text{Perimeter} = 4\pi + 2(10) = 4\pi + 20; \quad \text{Ratio} = \frac{20\pi}{100\pi} = \frac{1}{5}
Sector perimeter requires adding the two straight radii to the arc length, and the ratio of sector area to total area is 1:51:5.

Anahtar Kavram

Arc Length and Sector Area of a Circle
Tahmini Süre:1m 30s
Soru 1403Soru
For a constant aa, consider the following linear equation in one variable xx:
a(x2)32x+14=(a3)x+512\frac{a(x - 2)}{3} - \frac{2x + 1}{4} = \frac{(a - 3)x + 5}{12}
Which of the following statements are true? Select all such statements.

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Cevap: If a=1a = 1, the equation has no solution for xx.; If a=1a = -1, then x=0x = 0.; If x=4x = 4, then a=5a = 5.

Cevap

The correct statements are the ones asserting that a=1a = 1 leaves the equation with no solution, a=1a = -1 leads to x=0x = 0, and x=4x = 4 requires a=5a = 5.
Multiplying the equation by 12 and simplifying yields 3(a1)x=8(a+1)3(a - 1)x = 8(a + 1). When a=1a = 1, the left side becomes 0 while the right side becomes 16, creating an inconsistent equation 0=160 = 16 with no solution. When a=1a = -1, the equation becomes 6x=0-6x = 0, which gives x=0x = 0. When x=4x = 4, substituting into the simplified equation gives 12(a1)=8(a+1)12(a - 1) = 8(a + 1), which simplifies to 4a=20    a=54a = 20 \implies a = 5.

Adım Adım Çözüm

1
Clear denominators by multiplying every term of the equation by the least common multiple, 12.
4a(x2)3(2x+1)=(a3)x+54a(x - 2) - 3(2x + 1) = (a - 3)x + 5
Eliminating fractional coefficients simplifies the distribution and collection of variable terms.
2
Expand products on both sides of the equation.
4ax8a6x3=ax3x+54ax - 8a - 6x - 3 = ax - 3x + 5
Applying the distributive property isolates individual algebraic terms.
3
Rearrange terms to collect all xx-terms on the left side and constant terms on the right side.
(4a6a+3)x=8a+8    3(a1)x=8(a+1)(4a - 6 - a + 3)x = 8a + 8 \implies 3(a - 1)x = 8(a + 1)
Factoring out xx provides the canonical linear form Ax=BA x = B.
4
Evaluate the given conditions for aa and xx against the canonical form 3(a1)x=8(a+1)3(a - 1)x = 8(a + 1).
For a=1a = 1: 0=160 = 16 (no solution). For a=5a = 5: 12x=48    x=412x = 48 \implies x = 4. For a=1a = -1: 6x=0    x=0-6x = 0 \implies x = 0. For x=4x = 4: 12(a1)=8(a+1)    a=512(a - 1) = 8(a + 1) \implies a = 5. For a=0a = 0: 3x=8    x=83-3x = 8 \implies x = -\frac{8}{3} (negative).
Direct substitution verifies which algebraic relationships hold true.

Anahtar Kavram

Linear equations in one variable containing symbolic parameters can be analyzed for existence of solutions, zero-roots, and explicit values by reducing to the form Ax=BA x = B.
Tahmini Süre:2m 30s
Soru 1404Soru

Which of the following values of xx satisfy the inequality 2x15x|2x - 1| \le 5 - x? Select all that apply.

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Cevap: 4-4; 1-1; 11

Cevap

The values of xx that satisfy the inequality are 4-4, 1-1, and 11.
Solving the compound inequality (5x)2x15x-(5 - x) \le 2x - 1 \le 5 - x yields the solution range 4x2-4 \le x \le 2. The candidate values 4-4, 1-1, and 11 all lie within this range, making them valid solutions.

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1
Determine the non-negativity constraint for the right-hand side expression.
Since an absolute value 2x1|2x - 1| must be non-negative, we must have 5x05 - x \ge 0, which simplifies to x5x \le 5.
An absolute value cannot be less than a negative number.
2
Rewrite the absolute value inequality 2x15x|2x - 1| \le 5 - x as a compound linear inequality.
(5x)2x15x-(5 - x) \le 2x - 1 \le 5 - x, which expands to 5+x2x15x-5 + x \le 2x - 1 \le 5 - x.
For any non-negative expression BB, AB|A| \le B is logically equivalent to BAB-B \le A \le B.
3
Solve the left-hand inequality 5+x2x1-5 + x \le 2x - 1.
Subtracting xx from both sides gives 5x1-5 \le x - 1. Adding 11 to both sides yields x4x \ge -4.
Isolating xx establishes the lower bound of the solution set.
4
Solve the right-hand inequality 2x15x2x - 1 \le 5 - x.
Adding xx to both sides gives 3x153x - 1 \le 5. Adding 11 yields 3x63x \le 6, so x2x \le 2.
Isolating xx establishes the upper bound of the solution set.
5
Intersect all constraints to find the valid domain for xx.
Combining x4x \ge -4, x2x \le 2, and x5x \le 5 gives the closed interval [4,2][-4, 2].
A valid value of xx must satisfy all component inequalities simultaneously.
6
Evaluate the candidate choices against the solution interval [4,2][-4, 2].
The values 4-4, 1-1, and 11 fall within [4,2][-4, 2], whereas 33 and 5-5 fall outside this interval.
Only numbers inside [4,2][-4, 2] satisfy the original inequality.

Anahtar Kavram

Solving Absolute Value Inequalities with Variable Expressions
Soru 1405Soru

If xx is a real number that satisfies both of the inequalities 3x+411|3x + 4| \ge 11 and x1<6|x - 1| < 6, which of the following could be the value of xx? Select all that apply.

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Cevap: 33; 55

Cevap

The values 3 and 5 satisfy both inequalities.
Solving the first inequality 3x+411|3x + 4| \ge 11 yields x5x \le -5 or x73x \ge \frac{7}{3}. Solving the second inequality x1<6|x - 1| < 6 yields 5<x<7-5 < x < 7. Intersecting these two regions, the interval x5x \le -5 does not overlap with 5<x<7-5 < x < 7 because 5-5 is excluded from the second inequality. The overlap occurs only for 73x<7\frac{7}{3} \le x < 7. Among the choices, 3 and 5 fall within this valid interval.

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1
Solve the absolute value inequality 3x+411|3x + 4| \ge 11.
x5x \le -5 or x73x \ge \frac{7}{3}.
An absolute value inequality of the form uk|u| \ge k (where k>0k > 0) splits into two separate inequalities: uku \ge k or uku \le -k. Solving 3x+4113x + 4 \ge 11 gives 3x7    x733x \ge 7 \implies x \ge \frac{7}{3}. Solving 3x+4113x + 4 \le -11 gives 3x15    x53x \le -15 \implies x \le -5.
2
Solve the absolute value inequality x1<6|x - 1| < 6.
5<x<7-5 < x < 7.
An absolute value inequality of the form u<k|u| < k is equivalent to the compound inequality k<u<k-k < u < k. Thus, 6<x1<6-6 < x - 1 < 6. Adding 1 to all parts yields 5<x<7-5 < x < 7.
3
Determine the intersection of the two solution sets.
73x<7\frac{7}{3} \le x < 7.
The portion x5x \le -5 has no overlap with 5<x<7-5 < x < 7 because 5-5 is excluded by the strict inequality in the second condition. The portion x73x \ge \frac{7}{3} overlaps with 5<x<7-5 < x < 7 to yield the interval [73,7)[\frac{7}{3}, 7).
4
Evaluate which of the given options fall inside [73,7)[\frac{7}{3}, 7).
The numbers 3 and 5 belong to the interval, while 5-5, 3-3, and 77 do not.
Since 732.33\frac{7}{3} \approx 2.33, the values 3 and 5 fall strictly between 2.33 and 7.

Anahtar Kavram

Solving systems of linear absolute value inequalities by finding the intersection of compound solution intervals
Soru 1406Soru

If xx is a real number that satisfies both 32x5|3 - 2x| \ge 5 and 73x2>1\frac{7 - 3x}{-2} > -1, which of the following expresses all possible values of xx?

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Cevap: x4x \ge 4

Cevap

The condition is satisfied by all values of xx such that x4x \ge 4.
Solving 32x5|3 - 2x| \ge 5 yields two separate intervals: x1x \le -1 or x4x \ge 4. Solving 73x2>1\frac{7 - 3x}{-2} > -1 involves multiplying by 2-2 and dividing by 3-3, both of which flip the inequality sign, leading to x>53x > \frac{5}{3}. The values of xx that satisfy both constraints are those in the overlap of x(,1][4,)x \in (-\infty, -1] \cup [4, \infty) and x>53x > \frac{5}{3}, which simplifies directly to x4x \ge 4.

Adım Adım Çözüm

1
Solve the absolute value inequality 32x5|3 - 2x| \ge 5.
Splitting into two cases: 32x5    2x2    x13 - 2x \ge 5 \implies -2x \ge 2 \implies x \le -1, or 32x5    2x8    x43 - 2x \le -5 \implies -2x \le -8 \implies x \ge 4. So x(,1][4,)x \in (-\infty, -1] \cup [4, \infty).
An absolute value inequality uk|u| \ge k (for k>0k > 0) decouples into uku \ge k or uku \le -k.
2
Solve the linear inequality 73x2>1\frac{7 - 3x}{-2} > -1.
Multiply both sides by 2-2 (reversing the inequality): 73x<27 - 3x < 2. Subtract 7: 3x<5-3x < -5. Divide by 3-3 (reversing the inequality again): x>53x > \frac{5}{3}.
Multiplying or dividing an inequality by a negative quantity reverses the direction of the inequality sign.
3
Find the intersection of the two solution sets.
We require x((,1][4,))(53,)x \in ((-\infty, -1] \cup [4, \infty)) \cap (\frac{5}{3}, \infty). Since (,1](-\infty, -1] has no overlap with (53,)(\frac{5}{3}, \infty), the intersection is [4,)[4, \infty), or x4x \ge 4.
A real number must satisfy both inequalities simultaneously.

Anahtar Kavram

Solving systems of absolute value and linear inequalities with negative multipliers
Soru 1407Soru

A store manager recorded the number of orders processed online each day during a one-week period: 1414, 77, 2525, 1111, 1818, 22, and 1616. What is the median number of daily online orders processed during this week?

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Cevap: 1414

Cevap

The median number of daily online orders is 1414.
To find the median, the seven numbers must first be placed in ascending order: 2,7,11,14,16,18,252, 7, 11, 14, 16, 18, 25. Since there is an odd number of data points (77), the median is the single middle value located at the 4th position, which is 1414.

Adım Adım Çözüm

1
Arrange the given dataset of seven numbers in ascending order.
The sorted dataset is 2,7,11,14,16,18,252, 7, 11, 14, 16, 18, 25.
To determine the median of any dataset, the numerical values must first be ordered from smallest to largest.
2
Find the position of the middle element for a dataset with n=7n = 7 values.
The median position is 7+12=4\frac{7 + 1}{2} = 4.
When a dataset contains an odd number of elements nn, the median is located at the n+12\frac{n+1}{2}-th position.
3
Identify the 4th element in the sorted list.
The 4th element is 1414.
In the ordered sequence 2,7,11,14,16,18,252, 7, 11, 14, 16, 18, 25, the 4th entry is 1414.

Anahtar Kavram

The median is the middle value in a set of numerical data that has been arranged in ascending or descending order.
Soru 1408Soru
For all non-zero real numbers xx, the function ff satisfies the functional equation
f(x)+2f(1x)=3xf(x) + 2f\left(-\frac{1}{x}\right) = 3x

Which of the following statements must be true for all x0x \neq 0? Select all such statements.

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Cevap: f(1)=3f(-1) = 3; f(x)22f(x) \leq -2\sqrt{2} for all x>0x > 0

Cevap

The statements stating that f(1)=3f(-1) = 3 and that f(x)22f(x) \leq -2\sqrt{2} for all x>0x > 0 are the correct choices.
Solving the functional equation yields f(x)=x2xf(x) = -x - \frac{2}{x}. Substituting x=1x = -1 gives f(1)=3f(-1) = 3, making the statement asserting f(1)=3f(-1) = 3 correct. Furthermore, for any positive real number xx, the sum x+2x22x + \frac{2}{x} \geq 2\sqrt{2} by the AM-GM inequality, so f(x)=(x+2x)22f(x) = -\left(x + \frac{2}{x}\right) \leq -2\sqrt{2}, making the statement asserting f(x)22f(x) \leq -2\sqrt{2} for all x>0x > 0 correct.

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1
Set up a system of functional equations by substituting x1xx \to -\frac{1}{x}.
Replacing xx with 1x-\frac{1}{x} in the original equation f(x)+2f(1x)=3xf(x) + 2f\left(-\frac{1}{x}\right) = 3x gives f(1x)+2f(x)=3(1x)=3xf\left(-\frac{1}{x}\right) + 2f(x) = 3\left(-\frac{1}{x}\right) = -\frac{3}{x}.
This creates a system of two linear algebraic equations with two unknowns: f(x)f(x) and f(1x)f\left(-\frac{1}{x}\right).
2
Solve the system of equations for f(x)f(x).
Multiply the second equation by 22 to obtain 4f(x)+2f(1x)=6x4f(x) + 2f\left(-\frac{1}{x}\right) = -\frac{6}{x}. Subtracting the first equation f(x)+2f(1x)=3xf(x) + 2f\left(-\frac{1}{x}\right) = 3x from this gives 3f(x)=3x6x3f(x) = -3x - \frac{6}{x}, so f(x)=x2xf(x) = -x - \frac{2}{x}.
Eliminating the composite term f(1x)f\left(-\frac{1}{x}\right) yields an explicit expression for f(x)f(x).
3
Evaluate f(1)f(-1).
f(1)=(1)21=1+2=3f(-1) = -(-1) - \frac{2}{-1} = 1 + 2 = 3.
This confirms that the statement asserting f(1)=3f(-1) = 3 is correct.
4
Analyze the maximum value of f(x)f(x) for x>0x > 0 using the AM-GM inequality.
For x>0x > 0, x+2x2x2x=22x + \frac{2}{x} \geq 2\sqrt{x \cdot \frac{2}{x}} = 2\sqrt{2}. Therefore, f(x)=(x+2x)22f(x) = -\left(x + \frac{2}{x}\right) \leq -2\sqrt{2}.
This confirms that the statement asserting f(x)22f(x) \leq -2\sqrt{2} for all x>0x > 0 is correct.

Anahtar Kavram

Solving functional equations via variable substitution and analyzing function bounds via the AM-GM inequality.
Tahmini Süre:2m 30s
Soru 1409Soru

In a geometric plane, straight lines L1L_1 and L2L_2 intersect at point PP. The measure of the obtuse angle formed by the intersection of L1L_1 and L2L_2 is (5x10)(5x - 10)^\circ, and the measure of an adjacent acute angle is (2x+15)(2x + 15)^\circ. Ray PQPQ originates from point PP, is perpendicular to line L1L_1, and lies entirely within the interior of the (5x10)(5x - 10)^\circ obtuse angle. What is the measure, in degrees, of the angle formed between ray PQPQ and line L2L_2?

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Cevap: 2525^\circ

Cevap

2525^\circ
Two intersecting lines form adjacent angles that sum to 180180^\circ. Solving (5x10)+(2x+15)=180(5x - 10) + (2x + 15) = 180 gives 7x+5=1807x + 5 = 180, so x=25x = 25. The obtuse angle measure is 5(25)10=1155(25) - 10 = 115^\circ. Since ray PQPQ is perpendicular to line L1L_1, it forms a 9090^\circ angle with line L1L_1. The remaining angle between ray PQPQ and line L2L_2 within the obtuse angle region is 11590=25115^\circ - 90^\circ = 25^\circ.

Adım Adım Çözüm

1
Set up an algebraic equation using the supplementary angle relationship.
(5x10)+(2x+15)=180(5x - 10) + (2x + 15) = 180
Adjacent angles formed by two intersecting straight lines lie on a straight line and are supplementary, summing to 180180^\circ.
2
Solve for the variable xx.
7x+5=180    7x=175    x=257x + 5 = 180 \implies 7x = 175 \implies x = 25
Combining like terms simplifies the linear equation.
3
Calculate the degree measure of the obtuse angle.
Obtuse angle = 5(25)10=12510=1155(25) - 10 = 125 - 10 = 115^\circ
Substitute x=25x = 25 back into the expression (5x10)(5x - 10)^\circ.
4
Calculate the angle between ray PQPQ and line L2L_2.
Angle = 11590=25115^\circ - 90^\circ = 25^\circ
Ray PQPQ is perpendicular to line L1L_1 (9090^\circ) and lies inside the 115115^\circ angle, dividing the obtuse angle into a 9090^\circ portion and the remaining angle adjacent to line L2L_2.

Anahtar Kavram

Supplementary angles on a straight line and angle subtraction with perpendicular rays
Tahmini Süre:1m 30s
Soru 1410Soru

If xx is an integer that satisfies both 4x513|4x - 5| \le 13 and 2x131\frac{2x - 1}{-3} \le -1, what is the sum of all possible values of xx?

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Cevap: 9

Cevap

9
Solving the absolute value inequality 4x513|4x - 5| \le 13 yields 134x513-13 \le 4x - 5 \le 13, which simplifies to 2x4.5-2 \le x \le 4.5. Next, solving 2x131\frac{2x - 1}{-3} \le -1 requires multiplying both sides by 3-3 and reversing the inequality sign, giving 2x132x - 1 \ge 3, which simplifies to x2x \ge 2. Combining 2x4.5-2 \le x \le 4.5 and x2x \ge 2 for integer xx gives the set {2,3,4}\{2, 3, 4\}. The sum of these values is 2+3+4=92 + 3 + 4 = 9.

Adım Adım Çözüm

1
Solve the absolute value inequality 4x513|4x - 5| \le 13
-13 \le 4x - 5 \le 13 \implies -8 \le 4x \le 18 \implies -2 \le x \le 4.5
An absolute value inequality uk|u| \le k unfolds into the compound inequality kuk-k \le u \le k.
2
Solve the linear inequality 2x131\frac{2x - 1}{-3} \le -1
2x - 1 \ge 3 \implies 2x \ge 4 \implies x \ge 2
Multiplying or dividing both sides of an inequality by a negative number reverses the direction of the inequality sign.
3
Find the intersection of the two solution sets for integer xx
x \in \{2, 3, 4\}
The integers satisfying both 2x4.5-2 \le x \le 4.5 and x2x \ge 2 are 2, 3, and 4.
4
Calculate the sum of the possible integer values
2 + 3 + 4 = 9
Summing the valid integer solutions yields the final requested answer.

Anahtar Kavram

Linear Inequalities and Absolute Value
Tahmini Süre:2m 0s
Soru 1411Soru

A sector of a circle has an area of 15π15\pi square units and a perimeter of 10+6π10 + 6\pi units. What is the measure of the central angle of the sector, in degrees?

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Cevap: 216216^\circ

Cevap

The correct answer is 216216^\circ, corresponding to the option stating 216216^\circ.
The perimeter of a sector is defined as 2r+s=10+6π2r + s = 10 + 6\pi, which yields a radius of r=5r = 5 and an arc length s=6πs = 6\pi. Checking with the sector area formula 12rs=12(5)(6π)=15π\frac{1}{2}rs = \frac{1}{2}(5)(6\pi) = 15\pi confirms these measurements. The total area of the circle is π(5)2=25π\pi (5)^2 = 25\pi. The sector thus constitutes 15π25π=35\frac{15\pi}{25\pi} = \frac{3}{5} of the circle. Multiplying this fraction by 360360^\circ gives a central angle of 216216^\circ.

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1
Express the sector perimeter formula and solve for radius and arc length.
Radius r=5r = 5 and arc length s=6πs = 6\pi.
The perimeter of a sector equals two radii plus its arc length: Perimeter=2r+s=10+6π\text{Perimeter} = 2r + s = 10 + 6\pi. Equating standard and π\pi-termed components gives 2r=10    r=52r = 10 \implies r = 5 and arc length s=6πs = 6\pi.
2
Verify consistency using the sector area formula.
Area=15π\text{Area} = 15\pi, matching the given information.
The area of a sector can also be calculated as 12rs=12(5)(6π)=15π\frac{1}{2} r s = \frac{1}{2}(5)(6\pi) = 15\pi.
3
Find the total area of the circle and the fraction of the circle occupied by the sector.
Total area =25π= 25\pi, area fraction =35= \frac{3}{5}.
The full circle area is πr2=π(52)=25π\pi r^2 = \pi (5^2) = 25\pi. The sector represents 15π25π=35\frac{15\pi}{25\pi} = \frac{3}{5} of the entire circle.
4
Calculate the central angle θ\theta in degrees.
θ=216\theta = 216^\circ.
Multiply the fraction by 360360^\circ: θ=35×360=216\theta = \frac{3}{5} \times 360^\circ = 216^\circ.

Anahtar Kavram

Perimeter, Arc Length, and Area of a Circle Sector
Soru 1412Soru

If xx and yy are real numbers greater than 11 such that xy=yxx^{\sqrt{y}} = y^{\sqrt{x}} and x3=y2x^3 = y^2, what is the value of xx?

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Cevap: 8116\frac{81}{16}

Cevap

The correct answer is 8116\frac{81}{16}.
Expressing yy as x3/2x^{3/2} and substituting it into xy=yxx^{\sqrt{y}} = y^{\sqrt{x}} transforms the equation into xx3/4=x32x1/2x^{x^{3/4}} = x^{\frac{3}{2}x^{1/2}}. Equating exponents yields x3/4=32x1/2x^{3/4} = \frac{3}{2}x^{1/2}, which simplifies to x1/4=32x^{1/4} = \frac{3}{2}. Raising both sides to the fourth power gives x=8116x = \frac{81}{16}.

Adım Adım Çözüm

1
Express yy in terms of xx using the second given equation.
Since x>1x > 1 and y>1y > 1, taking the square root of both sides of y2=x3y^2 = x^3 gives y=x3/2y = x^{3/2}.
Converting yy to an exponential expression of xx allows single-variable substitution into the first equation.
2
Substitute y=x3/2y = x^{3/2} into the first equation xy=yxx^{\sqrt{y}} = y^{\sqrt{x}}.
Note that y=x3/2=(x3/2)1/2=x3/4\sqrt{y} = \sqrt{x^{3/2}} = (x^{3/2})^{1/2} = x^{3/4}. Thus, the left side becomes xx3/4x^{x^{3/4}}, and the right side becomes (x3/2)x=x32x1/2(x^{3/2})^{\sqrt{x}} = x^{\frac{3}{2}x^{1/2}}.
Applying exponent rules (am)n=amn(a^m)^n = a^{mn} simplifies both sides to base xx expressions.
3
Equate the exponents since the bases are equal and greater than 1.
x3/4=32x1/2x^{3/4} = \frac{3}{2}x^{1/2}.
If xa=xbx^a = x^b for x>1x > 1, then a=ba = b.
4
Divide both sides by x1/2x^{1/2} to isolate the power of xx.
x3/4x1/2=32    x3/41/2=32    x1/4=32\frac{x^{3/4}}{x^{1/2}} = \frac{3}{2} \implies x^{3/4 - 1/2} = \frac{3}{2} \implies x^{1/4} = \frac{3}{2}.
Using the quotient rule for exponents, xaxb=xab\frac{x^a}{x^b} = x^{a-b} where 3/41/2=1/43/4 - 1/2 = 1/4.
5
Raise both sides to the 4th power to solve for xx.
x=(32)4=3424=8116x = \left(\frac{3}{2}\right)^4 = \frac{3^4}{2^4} = \frac{81}{16}.
Raising (x1/4)4(x^{1/4})^4 eliminates the fractional exponent to give xx.

Anahtar Kavram

Solving systems of exponential equations using fractional exponent rules and base equality properties.
Soru 1413Soru

A container originally holds a liquid mixture consisting of substance A and substance B, where substance A constitutes 25\frac{2}{5} of the total volume. After 1515 liters of substance B are added to the container and 33 liters of substance A evaporate, the volume of substance A in the container becomes 14\frac{1}{4} of the new total liquid volume. What was the original total volume, in liters, of the liquid mixture in the container?

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Cevap: 40

Cevap

40 liters
Letting VV represent the original volume of the liquid mixture in liters, the initial amount of substance A is 25V\frac{2}{5}V. After adding 15 liters of substance B and losing 3 liters of substance A to evaporation, the updated volume of substance A is 25V3\frac{2}{5}V - 3, and the updated total volume is V+153=V+12V + 15 - 3 = V + 12. Setting up the relationship 25V3=14(V+12)\frac{2}{5}V - 3 = \frac{1}{4}(V + 12) and expanding the right side gives 25V3=14V+3\frac{2}{5}V - 3 = \frac{1}{4}V + 3. Subtracting 14V\frac{1}{4}V from both sides yields 320V=6\frac{3}{20}V = 6, which solves to V=40V = 40 liters.

Adım Adım Çözüm

1
Define the unknown variable and express initial quantities algebraically.
Let VV be the original total volume of the liquid mixture in liters. The original volume of substance A is 25V\frac{2}{5}V.
Establishing a variable for the initial total volume allows all changes to be modeled in terms of one variable.
2
Express the modified quantities after additions and evaporation.
New volume of substance A =25V3= \frac{2}{5}V - 3. New total volume =V+153=V+12= V + 15 - 3 = V + 12.
Adding 15 liters of substance B increases the total volume by 15, and losing 3 liters of substance A decreases both substance A and the total volume by 3.
3
Set up the linear equation based on the given ratio condition.
\frac{2}{5}V - 3 = \frac{1}{4}(V + 12)
Substance A forms one-fourth of the updated total liquid volume.
4
Expand and solve the linear equation for VV.
\frac{2}{5}V - 3 = \frac{1}{4}V + 3 \implies \frac{2}{5}V - \frac{1}{4}V = 6 \implies \frac{8 - 5}{20}V = 6 \implies \frac{3}{20}V = 6 \implies V = 40.
Clearing terms and subtracting 14V\frac{1}{4}V from 25V\frac{2}{5}V gives 320V=6\frac{3}{20}V = 6, which yields V=40V = 40.

Anahtar Kavram

Linear Equations in One Variable
Soru 1414Soru

If xx and yy are positive real numbers such that (x1y23x3y2)34=xayb\left(\frac{x^{-1}y^{\frac{2}{3}}}{\sqrt{x^3 y^{-2}}}\right)^{-\frac{3}{4}} = x^a y^b, what is the value of a+ba + b?

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Cevap: 58\frac{5}{8}

Cevap

The value of a+ba + b is 58\frac{5}{8}.
Simplifying the fraction inside the parentheses gives x52y53x^{-\frac{5}{2}} y^{\frac{5}{3}}. Raising this to the power of 34-\frac{3}{4} produces x158y54x^{\frac{15}{8}} y^{-\frac{5}{4}}. Equating exponents yields a=158a = \frac{15}{8} and b=54=108b = -\frac{5}{4} = -\frac{10}{8}. Adding these together gives a+b=58a + b = \frac{5}{8}.

Adım Adım Çözüm

1
Rewrite the radical expression in the denominator using fractional exponents.
x3y2=(x3y2)12=x32y1\sqrt{x^3 y^{-2}} = (x^3 y^{-2})^{\frac{1}{2}} = x^{\frac{3}{2}} y^{-1}
Applying the power rule (uv)w=uvw(u^v)^w = u^{v \cdot w} to radical expressions converts square roots to fractional exponents of 12\frac{1}{2}.
2
Simplify the expression inside the main parentheses by combining like base exponents.
\frac{x^{-1}y^{\frac{2}{3}}}{x^{\frac{3}{2}} y^{-1}} = x^{-1 - \frac{3}{2}} y^{\frac{2}{3} - (-1)} = x^{-\frac{5}{2}} y^{\frac{5}{3}}
When dividing exponential expressions with the same base, subtract the denominator exponent from the numerator exponent.
3
Apply the outer exponent 34-\frac{3}{4} to each factor inside the parentheses.
(x^{-\frac{5}{2}} y^{\frac{5}{3}})^{-\frac{3}{4}} = x^{(-\frac{5}{2})(-\frac{3}{4})} y^{(\frac{5}{3})(-\frac{3}{4})} = x^{\frac{15}{8}} y^{-\frac{5}{4}}
According to exponent rules, (uv)p=upvp(u \cdot v)^p = u^p \cdot v^p and (up)q=upq(u^p)^q = u^{p \cdot q}.
4
Identify aa and bb and calculate their sum a+ba + b.
a = \frac{15}{8}, \quad b = -\frac{5}{4} = -\frac{10}{8} \implies a + b = \frac{15}{8} - \frac{10}{8} = \frac{5}{8}
Match the simplified expression with xaybx^a y^b and add the resulting fractional exponents using a common denominator.

Anahtar Kavram

Simplifying nested algebraic expressions with negative and rational exponents using fundamental laws of exponents.
Tahmini Süre:2m 0s
Soru 1415Soru

In a circle centered at point OO with radius RR, radii OAOA and OBOB bound a sector AOBAOB with a central angle of 120120^\circ. Point PP lies on minor arc ABAB such that the ratio of the length of arc APAP to the length of arc PBPB is 1:31:3. Segment PQPQ is drawn perpendicular to radius OAOA, intersecting OAOA at point QQ. What is the ratio of the area of the region bounded by line segment PQPQ, line segment AQAQ, and minor arc APAP to the area of sector AOBAOB?

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Cevap: 4π3316π\frac{4\pi - 3\sqrt{3}}{16\pi}

Cevap

4π3316π\frac{4\pi - 3\sqrt{3}}{16\pi}
The correct answer 4π3316π\frac{4\pi - 3\sqrt{3}}{16\pi} is obtained by finding the central angle of sector AOPAOP (3030^\circ), subtracting the area of right triangle OQPOQP (316R2\frac{\sqrt{3}}{16}R^2) from the area of sector AOPAOP (π12R2\frac{\pi}{12}R^2), and dividing this bounded area by the total sector AOBAOB area (π3R2\frac{\pi}{3}R^2).

Adım Adım Çözüm

1
Determine the central angle AOP\angle AOP of sector AOPAOP
AOP=11+3×120=30\angle AOP = \frac{1}{1+3} \times 120^\circ = 30^\circ
Arc length is directly proportional to central angle. A 1:31:3 ratio means sector AOPAOP represents 14\frac{1}{4} of the 120120^\circ central angle.
2
Calculate the area of sector AOPAOP and the total area of sector AOBAOB
Area(Sector AOP)=30360πR2=π12R2\text{Area(Sector } AOP) = \frac{30^\circ}{360^\circ} \pi R^2 = \frac{\pi}{12} R^2, and Area(Sector AOB)=120360πR2=π3R2\text{Area(Sector } AOB) = \frac{120^\circ}{360^\circ} \pi R^2 = \frac{\pi}{3} R^2
The area of a sector with central angle θ\theta is θ360πR2\frac{\theta}{360^\circ} \pi R^2.
3
Calculate the area of right triangle OQPOQP
Area(OQP)=316R2\text{Area}(\triangle OQP) = \frac{\sqrt{3}}{16} R^2
In OQP\triangle OQP, QOP=30\angle QOP = 30^\circ and hypotenuse OP=ROP = R. Thus OQ=Rcos(30)=R32OQ = R \cos(30^\circ) = \frac{R\sqrt{3}}{2} and PQ=Rsin(30)=R2PQ = R \sin(30^\circ) = \frac{R}{2}. Area=12×OQ×PQ=12(R32)(R2)=316R2\text{Area} = \frac{1}{2} \times OQ \times PQ = \frac{1}{2} \left(\frac{R\sqrt{3}}{2}\right)\left(\frac{R}{2}\right) = \frac{\sqrt{3}}{16} R^2.
4
Calculate the area of the bounded region and take the ratio to the area of sector AOBAOB
Ratio=π12R2316R2π3R2=4π3316π\text{Ratio} = \frac{\frac{\pi}{12}R^2 - \frac{\sqrt{3}}{16}R^2}{\frac{\pi}{3}R^2} = \frac{4\pi - 3\sqrt{3}}{16\pi}
Subtract the triangle area from sector AOPAOP area to get the bounded region area, then divide by sector AOBAOB area.

Anahtar Kavram

Sector Area, Arc Length Proportions, and Geometric Region Subdivision
Tahmini Süre:3m 0s
Soru 1416Soru

What is the least integer value of xx that satisfies the inequality 4x511|4x - 5| \le 11?

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Cevap: -1

Cevap

The least integer value of xx that satisfies the inequality is 1-1.
Expanding the absolute value inequality 4x511|4x - 5| \le 11 produces 114x511-11 \le 4x - 5 \le 11. Adding 5 across all sections yields 64x16-6 \le 4x \le 16, and dividing by 4 results in 1.5x4-1.5 \le x \le 4. The set of integers within this range is {1,0,1,2,3,4}\{-1, 0, 1, 2, 3, 4\}, making 1-1 the least integer value.

Adım Adım Çözüm

1
Rewrite the absolute value inequality as a double inequality.
114x511-11 \le 4x - 5 \le 11
An absolute value inequality of the form ua|u| \le a for a0a \ge 0 is equivalent to aua-a \le u \le a.
2
Add 5 to all parts of the compound inequality.
64x16-6 \le 4x \le 16
To isolate xx, first add 5 to eliminate the constant term 5-5.
3
Divide all parts by 4.
1.5x4-1.5 \le x \le 4
Dividing by a positive constant preserves the direction of the inequality signs.
4
Select the minimum integer contained within the solution interval [1.5,4][-1.5, 4].
1-1
The integer values satisfying 1.5x4-1.5 \le x \le 4 are 1,0,1,2,3,4-1, 0, 1, 2, 3, 4. The smallest among these is 1-1.

Anahtar Kavram

Linear inequalities involving absolute value
Soru 1417Soru

What is the sum of all real solutions to the equation 3x+10x=2\sqrt{3x + 10} - x = 2?

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Cevap: 22

Cevap

The sum of all real solutions is 22.
To solve 3x+10x=2\sqrt{3x + 10} - x = 2, isolate the radical to get 3x+10=x+2\sqrt{3x + 10} = x + 2. Squaring both sides yields 3x+10=x2+4x+43x + 10 = x^2 + 4x + 4. Rearranging into standard quadratic form gives x2+x6=0x^2 + x - 6 = 0, which factors as (x+3)(x2)=0(x + 3)(x - 2) = 0, yielding candidates x=2x = 2 and x=3x = -3. Substituting x=2x = 2 into the original equation yields 162=2\sqrt{16} - 2 = 2, which is true. Substituting x=3x = -3 yields 1(3)=42\sqrt{1} - (-3) = 4 \neq 2, so x=3x = -3 is extraneous. The only valid solution is x=2x = 2, so the sum of all valid solutions is 22.

Adım Adım Çözüm

1
Isolate the radical expression on one side of the equation
3x+10=x+2\sqrt{3x + 10} = x + 2
Isolating the radical allows squaring both sides cleanly to eliminate the radical sign.
2
Square both sides of the equation
3x+10=(x+2)2=x2+4x+43x + 10 = (x + 2)^2 = x^2 + 4x + 4
Squaring eliminates the square root, converting the equation into a polynomial form.
3
Rearrange terms into standard quadratic form ax2+bx+c=0ax^2 + bx + c = 0
x2+x6=0x^2 + x - 6 = 0
Grouping all terms on one side sets up the equation for factoring.
4
Factor the quadratic equation to find candidate solutions
(x+3)(x2)=0    x=3 or x=2(x + 3)(x - 2) = 0 \implies x = -3 \text{ or } x = 2
Factoring determines the values of xx that solve the algebraic polynomial.
5
Test candidate solutions in the original radical equation to filter extraneous roots
For x=2x = 2: 3(2)+102=162=42=2\sqrt{3(2) + 10} - 2 = \sqrt{16} - 2 = 4 - 2 = 2 (Valid). For x=3x = -3: 3(3)+10(3)=1+3=42\sqrt{3(-3) + 10} - (-3) = \sqrt{1} + 3 = 4 \neq 2 (Extraneous). Thus, x=2x = 2 is the only valid solution.
Squaring an equation can introduce extraneous roots that do not satisfy the original principal root definition.

Anahtar Kavram

Solving Radical Equations and Filtering Extraneous Roots
Tahmini Süre:1m 30s
Soru 1418Soru

A coffee shop owner creates a 3030-pound blend of coffee by mixing Bean X, which costs $8\$8 per pound, with Bean Y, which costs $14\$14 per pound. If the final mixture costs $10\$10 per pound, how many pounds of Bean X are in the mixture?

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Cevap: 20

Cevap

The mixture contains 20 pounds of Bean X.
The quantity of Bean X required is 20 pounds. Setting up the cost equation 8x+14(30x)=3008x + 14(30 - x) = 300 simplifies to 6x=120-6x = -120, giving x=20x = 20.

Adım Adım Çözüm

1
Define the unknown variables representing the quantities of each component.
Let xx be the weight of Bean X in pounds. The weight of Bean Y is (30x)(30 - x) pounds.
Since the total weight of the mixture is 30 pounds, expressing Bean Y in terms of xx creates a single-variable system.
2
Set up a linear equation based on total financial value.
8x+14(30x)=10×308x + 14(30 - x) = 10 \times 30
The total cost of Bean X plus the total cost of Bean Y equals the total cost of the combined 30-pound mixture.
3
Solve the algebraic equation for xx.
8x+42014x=300    6x=120    x=208x + 420 - 14x = 300 \implies -6x = -120 \implies x = 20
Combining like terms isolates the variable xx to yield the required quantity of Bean X.

Anahtar Kavram

Linear mixture modeling and single-variable algebraic modeling
Soru 1419Soru

If xx is a real number that satisfies both 52x11|5 - 2x| \le 11 and 3x+7<1-3x + 7 < 1, what is the least possible integer value of xx?

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Cevap: 3

Cevap

The least possible integer value of xx is 3.
Solving 52x11|5 - 2x| \le 11 leads to 1152x11-11 \le 5 - 2x \le 11. Subtracting 5 gives 162x6-16 \le -2x \le 6, and dividing by 2-2 (flipping the inequalities) yields 3x8-3 \le x \le 8. Next, solving 3x+7<1-3x + 7 < 1 gives 3x<6-3x < -6, which upon dividing by 3-3 (and flipping the inequality sign) gives x>2x > 2. Combining these two requirements yields 2<x82 < x \le 8. The integer values satisfying this inequality are 3, 4, 5, 6, 7, and 8. The least possible integer value among these is 3.

Adım Adım Çözüm

1
Solve the absolute value inequality 52x11|5 - 2x| \le 11.
1152x11    162x6    3x8-11 \le 5 - 2x \le 11 \implies -16 \le -2x \le 6 \implies -3 \le x \le 8.
An absolute value inequality uk|u| \le k expands to kuk-k \le u \le k. Dividing by 2-2 flips the inequality direction.
2
Solve the linear inequality 3x+7<1-3x + 7 < 1.
3x<6    x>2-3x < -6 \implies x > 2.
Subtract 7 from both sides, then divide by 3-3, remembering to reverse the inequality sign.
3
Determine the intersection of both solution sets.
2<x82 < x \le 8.
xx must be strictly greater than 2 and less than or equal to 8.
4
Identify the smallest integer within the range 2<x82 < x \le 8.
3
Since x>2x > 2 is strict, 2 is excluded, making 3 the smallest integer in the range.

Anahtar Kavram

Solving systems of linear inequalities involving absolute values and correctly applying sign-flipping rules when multiplying or dividing by negative quantities.

Alternatif Yöntem

Test integer candidates directly: for x=2x = 2, 3(2)+7=1-3(2) + 7 = 1, which is not strictly less than 1. For x=3x = 3, 3(3)+7=2<1-3(3) + 7 = -2 < 1 (valid) and 52(3)=1=111|5 - 2(3)| = |-1| = 1 \le 11 (valid), confirming 3 is the smallest integer solution.
Tahmini Süre:1m 30s
Soru 1420Soru

If 5x+318-5x + 3 \le 18, which of the following inequalities represents all possible real values of xx?

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Cevap: x3x \ge -3

Cevap

x3x \ge -3
Subtracting 3 from both sides gives 5x15-5x \le 15. Dividing both sides by 5-5 requires flipping the inequality sign from \le to \ge, resulting in x3x \ge -3.

Adım Adım Çözüm

1
Subtract 3 from both sides of the inequality 5x+318-5x + 3 \le 18.
5x15-5x \le 15
Isolate the variable term on the left side.
2
Divide both sides by 5-5 and reverse the inequality sign from \le to \ge.
x3x \ge -3
Dividing an inequality by a negative number reverses the direction of the inequality sign.

Anahtar Kavram

Linear Inequalities and Sign Reversal
ÖncekiSayfa 71 / 107Sonraki
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