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Soru 2461Soru →

The table below shows coordinate points (x,y)(x, y) that lie on a line LL in the standard (x,y)(x, y) coordinate system:

xxyy
−2-2−7-7
1122
441111

What is the xx-intercept of line LL?

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Cevap: 13\frac{1}{3}

Cevap

The correct answer is 13\frac{1}{3}
The correct answer is 13\frac{1}{3}. First, find the slope of the line using the points (−2,−7)(-2, -7) and (1,2)(1, 2) from the table: m=2−(−7)1−(−2)=3m = \frac{2 - (-7)}{1 - (-2)} = 3. Next, substitute the slope and the coordinate point (1,2)(1, 2) into the point-slope equation to get y−2=3(x−1)y - 2 = 3(x - 1), which simplifies to y=3x−1y = 3x - 1. To find the xx-intercept, set y=0y = 0 and solve for xx: 0=3x−10 = 3x - 1, which gives x=13x = \frac{1}{3}.

Adım Adım Çözüm

1
Calculate the slope (mm) of line LL using the coordinate points (−2,−7)(-2, -7) and (1,2)(1, 2) from the table.
The slope is m=2−(−7)1−(−2)=93=3m = \frac{2 - (-7)}{1 - (-2)} = \frac{9}{3} = 3.
The slope of a line represents its constant rate of change and is calculated using the formula m=y2−y1x2−x1m = \frac{y_2 - y_1}{x_2 - x_1}.
2
Write the linear equation in slope-intercept form using the slope m=3m = 3 and the point (1,2)(1, 2).
Using the point-slope form: y−2=3(x−1)⇒y−2=3x−3⇒y=3x−1y - 2 = 3(x - 1) \Rightarrow y - 2 = 3x - 3 \Rightarrow y = 3x - 1.
Using point-slope form y−y1=m(x−x1)y - y_1 = m(x - x_1) allows us to easily simplify the relationship into slope-intercept form y=mx+by = mx + b.
3
Find the xx-intercept of the line by setting y=0y = 0 and solving the equation for xx.
Setting y=0y = 0 gives 0=3x−1⇒3x=1⇒x=130 = 3x - 1 \Rightarrow 3x = 1 \Rightarrow x = \frac{1}{3}.
The xx-intercept is the coordinate value where the graph intersects the xx-axis, which mathematically occurs when y=0y = 0.

Anahtar Kavram

Determining the equation of a line from tabular coordinates and calculating its intercepts
Soru 2462Soru →

An irregular convex hexagon has three interior angles that are congruent to each other, and the remaining three interior angles have measures in the ratio 3:4:53:4:5. If the sum of the measures of the three congruent angles is 360∘360^\circ, what is the degree measure of the largest interior angle of the hexagon?

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Cevap: 150∘150^\circ

Cevap

The degree measure of the largest interior angle of the hexagon is 150∘150^\circ.
The correct answer is 150∘150^\circ. The total sum of the interior angles of a hexagon is (6−2)×180∘=720∘(6-2) \times 180^\circ = 720^\circ. Subtracting the sum of the three congruent angles (360∘360^\circ) leaves 360∘360^\circ for the remaining three angles. With their measures in the ratio 3:4:53:4:5, we can write the equation 3x+4x+5x=360∘3x + 4x + 5x = 360^\circ, which simplifies to 12x=360∘12x = 360^\circ, giving x=30∘x = 30^\circ. The measures of these three angles are 90∘90^\circ, 120∘120^\circ, and 150∘150^\circ. The three congruent angles each measure 360∘/3=120∘360^\circ / 3 = 120^\circ. Comparing all six angles (120∘,120∘,120∘,90∘,120∘,150∘120^\circ, 120^\circ, 120^\circ, 90^\circ, 120^\circ, 150^\circ), the largest measure is 150∘150^\circ.

Adım Adım Çözüm

1
Calculate the sum of the interior angles of a convex hexagon.
720∘720^\circ
Using the formula (n−2)×180∘(n - 2) \times 180^\circ for a polygon with n=6n = 6 sides, the sum is (6−2)×180∘=4×180∘=720∘(6 - 2) \times 180^\circ = 4 \times 180^\circ = 720^\circ.
2
Determine the sum of the remaining three interior angles.
360∘360^\circ
We subtract the sum of the three congruent angles (360∘360^\circ) from the total sum of the hexagon's interior angles (720∘720^\circ): 720∘−360∘=360∘720^\circ - 360^\circ = 360^\circ.
3
Set up and solve an equation using the ratio of the remaining three angles.
x=30∘x = 30^\circ
Let the measures of the remaining three angles be 3x3x, 4x4x, and 5x5x. Their sum is 360∘360^\circ, so 3x+4x+5x=360∘  ⟹  12x=360∘  ⟹  x=30∘3x + 4x + 5x = 360^\circ \implies 12x = 360^\circ \implies x = 30^\circ.
4
Calculate the measures of all six interior angles to identify the largest one.
The angles are 120∘120^\circ, 120∘120^\circ, 120∘120^\circ, 90∘90^\circ, 120∘120^\circ, and 150∘150^\circ. The largest is 150∘150^\circ.
Each of the three congruent angles measures 360∘/3=120∘360^\circ / 3 = 120^\circ. The other three angles measure 3(30∘)=90∘3(30^\circ) = 90^\circ, 4(30∘)=120∘4(30^\circ) = 120^\circ, and 5(30∘)=150∘5(30^\circ) = 150^\circ. Comparing all these values, the maximum is 150∘150^\circ.

Anahtar Kavram

The sum of the interior angles of a convex nn-sided polygon is given by (n−2)×180∘(n-2) \times 180^\circ. Irregular polygons share this total sum, and ratio relationships can be solved by introducing a variable multiplier.
Soru 2463Soru →

The measures of five of the interior angles of a convex hexagon are in the ratio 3:4:5:6:73:4:5:6:7. The measure of the sixth interior angle is 30∘30^\circ less than the average measure of the other five angles. What is the degree measure of the largest interior angle of the hexagon?

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Cevap: 175∘175^\circ

Cevap

The correct answer is 175^\circ because solving the equation for the sum of the hexagon's interior angles yields a multiplier of x=25x = 25, making the largest angle 7x=175∘7x = 175^\circ.
The correct answer is 175° because the sum of the interior angles of a hexagon is (6−2)×180∘=720∘(6-2) \times 180^\circ = 720^\circ. Representing the five ratio-based angles as 3x3x, 4x4x, 5x5x, 6x6x, and 7x7x gives their sum as 25x25x and their average as 5x5x. The sixth angle is therefore 5x−305x - 30. Setting up the sum of all six angles yields 25x+(5x−30)=720  ⟹  30x=750  ⟹  x=2525x + (5x - 30) = 720 \implies 30x = 750 \implies x = 25. The largest angle is 7x=7(25)=175∘7x = 7(25) = 175^\circ.

Adım Adım Çözüm

1
Find the sum of the interior angles of a hexagon.
Sum = 720∘720^\circ
Using the interior angle sum formula S=(n−2)×180∘S = (n - 2) \times 180^\circ for a hexagon where n=6n = 6, we get S=(6−2)×180∘=4×180∘=720∘S = (6 - 2) \times 180^\circ = 4 \times 180^\circ = 720^\circ.
2
Express the five ratio-based angles in terms of a variable xx.
The angles are 3x3x, 4x4x, 5x5x, 6x6x, and 7x7x.
Since the measures of five angles are in the ratio 3:4:5:6:73:4:5:6:7, we can define them as multiples of a common scale factor xx.
3
Compute the average measure of these five angles in terms of xx.
Average = 5x5x
The sum of the five angles is 3x+4x+5x+6x+7x=25x3x + 4x + 5x + 6x + 7x = 25x. The average is the sum divided by the count: 25x5=5x\frac{25x}{5} = 5x.
4
Express the measure of the sixth angle in terms of xx.
Sixth angle = 5x−305x - 30
The sixth angle is described as being 30∘30^\circ less than the average of the other five angles, which we found to be 5x5x.
5
Write and solve the equation for the sum of all six interior angles.
x=25x = 25
The sum of all six angles must equal the total sum of 720∘720^\circ: 25x+(5x−30)=720  ⟹  30x−30=720  ⟹  30x=750  ⟹  x=2525x + (5x - 30) = 720 \implies 30x - 30 = 720 \implies 30x = 750 \implies x = 25.
6
Calculate the measure of the largest interior angle.
175∘175^\circ
The largest interior angle corresponds to the largest term in the ratio, which is 7x7x. Substituting x=25x = 25 yields 7×25=175∘7 \times 25 = 175^\circ.

Anahtar Kavram

Applying the interior angle sum formula for polygons combined with ratio and algebraic translation properties.

Alternatif Yöntem

Instead of using the sum of interior angles, one could use the sum of exterior angles, which is always 360∘360^\circ. The exterior angles corresponding to the five angles in ratio 3:4:5:6:73:4:5:6:7 would be 180−3x180 - 3x, 180−4x180 - 4x, 180−5x180 - 5x, 180−6x180 - 6x, and 180−7x180 - 7x. The sixth exterior angle is 180−(5x−30)=210−5x180 - (5x - 30) = 210 - 5x. Summing these six exterior angles: (180−3x)+(180−4x)+(180−5x)+(180−6x)+(180−7x)+(210−5x)=1110−30x=360(180 - 3x) + (180 - 4x) + (180 - 5x) + (180 - 6x) + (180 - 7x) + (210 - 5x) = 1110 - 30x = 360. Solving for xx yields 30x=750  ⟹  x=2530x = 750 \implies x = 25. The largest interior angle corresponds to the smallest exterior angle, which is 180−7x=180−7(25)=5∘180 - 7x = 180 - 7(25) = 5^\circ, giving the largest interior angle as 180−5=175∘180 - 5 = 175^\circ.
Tahmini Süre:3m 0s
Soru 2464Soru →

A student translates a word problem into an inequality. The problem states: "One-fourth of the difference of xx and 33 is greater than the sum of 11 and one-third of the quantity 2x2x minus 11." Which of the following inequalities represents the correct set of all real values of xx that satisfy this condition?

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Cevap: x<−175x < -\frac{17}{5}

Cevap

The set of all real values of xx satisfying the condition is x<−175x < -\frac{17}{5}.
The correct inequality is obtained by translating the word problem statement as x−34>1+2x−13\frac{x - 3}{4} > 1 + \frac{2x - 1}{3}. Multiplying the entire inequality by 1212 yields 3(x−3)>12+4(2x−1)3(x - 3) > 12 + 4(2x - 1). Distributing the coefficients results in 3x−9>12+8x−43x - 9 > 12 + 8x - 4, which simplifies to 3x−9>8x+83x - 9 > 8x + 8. Moving all terms containing xx to the left and constants to the right gives −5x>17-5x > 17. Dividing both sides by −5-5 and reversing the inequality sign results in the solution x<−175x < -\frac{17}{5}.

Adım Adım Çözüm

1
Translate the verbal description into an algebraic inequality.
x−34>1+2x−13\frac{x - 3}{4} > 1 + \frac{2x - 1}{3}
The phrase "one-fourth of the difference of xx and 33" translates to x−34\frac{x - 3}{4}, and "the sum of 11 and one-third of the quantity 2x2x minus 11" translates to 1+2x−131 + \frac{2x - 1}{3}.
2
Multiply all terms by the least common multiple of the denominators, which is 1212, to clear the fractions.
3(x−3)>12+4(2x−1)3(x - 3) > 12 + 4(2x - 1)
Multiplying both sides of an inequality by a positive number maintains the direction of the inequality sign while eliminating fractional coefficients.
3
Expand both sides of the inequality by distributing the coefficients.
3x−9>12+8x−43x - 9 > 12 + 8x - 4
Distribution allows the variable and constant terms to be separated and simplified.
4
Simplify the constants on the right side and move all variable terms to one side and constants to the other.
−5x>17-5x > 17
Subtracting 8x8x from both sides and adding 99 to both sides isolates the variable term on the left side of the inequality.
5
Divide both sides by −5-5 and reverse the inequality sign.
x<−175x < -\frac{17}{5}
Dividing or multiplying an inequality by a negative number reverses the direction of the inequality sign.

Anahtar Kavram

Solving linear inequalities by translating word problems and applying the sign-flip rule when dividing by a negative number.
Tahmini Süre:1m 30s
Soru 2465Soru →

A circle in the standard (x,y)(x, y) coordinate plane is described by the equation x2+y2=25x^2 + y^2 = 25. A line is described by the equation 3x−4y=c3x - 4y = c, where cc is a positive constant. If the system of these two equations has exactly one real solution for (x,y)(x, y), what is the value of cc?

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Cevap: 25

Cevap

The value of cc is 2525.
The correct answer is 2525. The equation x2+y2=25x^2 + y^2 = 25 represents a circle centered at (0,0)(0, 0) with a radius of 55. For the system of equations to have exactly one real solution, the line 3x−4y=c3x - 4y = c must be tangent to the circle. The perpendicular distance from the center (0,0)(0,0) to the line 3x−4y−c=03x - 4y - c = 0 is given by ∣3(0)−4(0)−c∣32+(−4)2=∣c∣5\frac{|3(0) - 4(0) - c|}{\sqrt{3^2 + (-4)^2}} = \frac{|c|}{5}. Setting this distance equal to the radius of the circle yields ∣c∣5=5\frac{|c|}{5} = 5, which gives ∣c∣=25|c| = 25. Since cc is specified as a positive constant, cc must be 2525.

Adım Adım Çözüm

1
Find the center and radius of the circle.
Center is (0,0)(0, 0) and radius is r=5r = 5.
The circle equation x2+y2=25x^2 + y^2 = 25 is in the standard form x2+y2=r2x^2 + y^2 = r^2 centered at the origin with radius r=25=5r = \sqrt{25} = 5.
2
Set up the condition for tangency (exactly one real solution).
The perpendicular distance from the center (0,0)(0,0) to the line 3x−4y−c=03x - 4y - c = 0 must equal the radius 55.
A line intersects a circle at exactly one point if and only if the line is tangent to the circle.
3
Apply the point-to-line distance formula.
Distance d=∣3(0)−4(0)−c∣32+(−4)2=∣c∣5d = \frac{|3(0) - 4(0) - c|}{\sqrt{3^2 + (-4)^2}} = \frac{|c|}{5}.
The formula for the distance from (x0,y0)(x_0, y_0) to the line Ax+By+C=0Ax + By + C = 0 is d=∣Ax0+By0+C∣A2+B2d = \frac{|Ax_0 + By_0 + C|}{\sqrt{A^2 + B^2}}.
4
Solve for the positive constant cc.
c=25c = 25
Setting the distance ∣c∣5\frac{|c|}{5} equal to the radius 55 gives ∣c∣=25|c| = 25. Since cc is a positive constant, c=25c = 25.

Anahtar Kavram

Determining conditions for tangency in a system of linear and circular equations.

Alternatif Yöntem

Instead of using the geometric distance formula, the system can be solved algebraically by substitution. Express yy in terms of xx from the linear equation: y=3x−c4y = \frac{3x - c}{4}. Substitute this expression into the circle's equation: x2+(3x−c4)2=25x^2 + \left(\frac{3x - c}{4}\right)^2 = 25. Expand the terms and multiply by 1616 to clear the denominator: 16x2+9x2−6cx+c2=40016x^2 + 9x^2 - 6cx + c^2 = 400, which simplifies to the quadratic equation 25x2−6cx+(c2−400)=025x^2 - 6cx + (c^2 - 400) = 0. For the system to have exactly one solution, this quadratic equation must have a discriminant equal to zero. Calculate the discriminant: D=(−6c)2−4(25)(c2−400)=36c2−100c2+40000=−64c2+40000=0D = (-6c)^2 - 4(25)(c^2 - 400) = 36c^2 - 100c^2 + 40000 = -64c^2 + 40000 = 0. Solving for cc yields 64c2=40000  ⟹  c2=62564c^2 = 40000 \implies c^2 = 625. Since cc is a positive constant, c=25c = 25.
Tahmini Süre:1m 30s
Soru 2466Soru →

The first term of an arithmetic sequence is 12\frac{1}{2}, and the second term is 56\frac{5}{6}. The first term of a geometric sequence is 222^2, and the common ratio is 232^3. Let AA be the third term of the arithmetic sequence, and let GG be the third term of the geometric sequence. If a third value, VV, is defined as 56\frac{5}{6} less than twice GG, what is the value of V+AV + A?

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Cevap: 15373\frac{1537}{3}

Cevap

15373\frac{1537}{3}
The correct answer is 15373\frac{1537}{3} because calculating the third term of the arithmetic sequence yields A=76A = \frac{7}{6} and the third term of the geometric sequence yields G=256G = 256. Translating the relationship for VV yields V=2(256)−56=512−56V = 2(256) - \frac{5}{6} = 512 - \frac{5}{6}. Finding the sum of VV and AA yields 512−56+76=51213=15373512 - \frac{5}{6} + \frac{7}{6} = 512\frac{1}{3} = \frac{1537}{3}.

Adım Adım Çözüm

1
Calculate the common difference dd of the arithmetic sequence.
d=a2−a1=56−12=13d = a_2 - a_1 = \frac{5}{6} - \frac{1}{2} = \frac{1}{3}
The common difference is the difference between any term and the preceding term in an arithmetic sequence.
2
Calculate the third term AA of the arithmetic sequence.
A=a1+2d=12+2(13)=76A = a_1 + 2d = \frac{1}{2} + 2\left(\frac{1}{3}\right) = \frac{7}{6}
The nn-th term of an arithmetic sequence is given by an=a1+(n−1)da_n = a_1 + (n-1)d.
3
Calculate the third term GG of the geometric sequence.
G=g1⋅r2=22⋅(23)2=22⋅26=28=256G = g_1 \cdot r^2 = 2^2 \cdot (2^3)^2 = 2^2 \cdot 2^6 = 2^8 = 256
The nn-th term of a geometric sequence is given by gn=g1⋅rn−1g_n = g_1 \cdot r^{n-1}.
4
Set up and solve for VV using the algebraic relationship described.
V=2G−56=2(256)−56=512−56V = 2G - \frac{5}{6} = 2(256) - \frac{5}{6} = 512 - \frac{5}{6}
The phrase '5/6 less than twice G' translates to 2G−562G - \frac{5}{6}.
5
Compute the sum of VV and AA.
V+A=(512−56)+76=512+26=512+13=15373V + A = \left(512 - \frac{5}{6}\right) + \frac{7}{6} = 512 + \frac{2}{6} = 512 + \frac{1}{3} = \frac{1537}{3}
Substitute the values of VV and AA and simplify the resulting fractional expression.

Anahtar Kavram

Arithmetic and Geometric Sequences and Series
Tahmini Süre:1m 30s
Soru 2467Soru →

One of the solutions to the quadratic equation 0.5x2+bx−6=00.5x^2 + bx - 6 = 0, where bb is a constant, is x=3x = 3. What is the value of the other solution?

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Cevap: -4

Cevap

The other solution to the quadratic equation is -4.
Substituting the given solution x=3x = 3 into the equation yields 0.5(3)2+3b−6=00.5(3)^2 + 3b - 6 = 0. Simplifying this expression gives 4.5+3b−6=04.5 + 3b - 6 = 0, which leads to 3b=1.53b = 1.5 and thus b=0.5b = 0.5. With b=0.5b = 0.5, the quadratic equation becomes 0.5x2+0.5x−6=00.5x^2 + 0.5x - 6 = 0. Multiplying the entire equation by 2 to obtain integer coefficients results in x2+x−12=0x^2 + x - 12 = 0. This quadratic factors into (x−3)(x+4)=0(x - 3)(x + 4) = 0, which gives the solutions x=3x = 3 and x=−4x = -4. Therefore, the other solution is −4-4. Alternatively, using Vieta's formulas, the product of the roots of a quadratic equation ax2+bx+c=0ax^2 + bx + c = 0 is equal to c/ac/a. Here, the product of the roots is −6/0.5=−12-6 / 0.5 = -12. Since one root is 33, the other root must be −12/3=−4-12 / 3 = -4.

Adım Adım Çözüm

1
Substitute the given solution x=3x = 3 into the quadratic equation to find the value of bb.
b=0.5b = 0.5
Since x=3x = 3 is a solution, it must satisfy the equation, allowing us to solve for the unknown coefficient bb.
2
Rewrite the equation using b=0.5b = 0.5 and simplify by multiplying all terms by 2.
x2+x−12=0x^2 + x - 12 = 0
Multiplying the equation by 2 eliminates the decimal coefficients, making the quadratic expression easier to factor.
3
Factor the quadratic equation to determine the roots.
x=3x = 3 or x=−4x = -4
The equation factors into (x−3)(x+4)=0(x - 3)(x + 4) = 0. Solving for xx yields the given root of 3 and the second root of -4.

Anahtar Kavram

Solving quadratic equations by utilizing a known solution to determine unknown coefficients, and applying factoring techniques or root relationships to find the remaining solution.
Tahmini Süre:1m 30s
Soru 2468Soru →

In rectangle PQRSPQRS, the length of side PQPQ is 8 inches and the length of diagonal PRPR is 10 inches. What is the length, in inches, of side QRQR?

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Cevap: 6

Cevap

The length of side QR is 6 inches.
The correct answer is 6. In a rectangle, all four interior angles are right angles (90 degrees). Therefore, triangle PQR is a right triangle with the right angle at Q. According to the Pythagorean theorem, the sum of the squares of the lengths of the legs is equal to the square of the length of the hypotenuse: PQ² + QR² = PR². Substituting the given values: 8² + QR² = 10², which simplifies to 64 + QR² = 100. Subtracting 64 from both sides gives QR² = 36. Taking the square root of both sides yields QR = 6 inches.

Adım Adım Çözüm

1
Identify the geometric relationship in rectangle PQRS.
Angle PQR is a right angle (90 degrees), which makes triangle PQR a right triangle with legs PQ and QR, and hypotenuse PR.
By definition, all interior angles of a rectangle are 90 degrees, and the diagonal connects opposite vertices, forming two right triangles.
2
Apply the Pythagorean theorem to triangle PQR.
PQ² + QR² = PR², which becomes 8² + QR² = 10².
The Pythagorean theorem states that in any right triangle, the sum of the squares of the leg lengths equals the square of the hypotenuse length.
3
Solve for the unknown side length QR.
64 + QR² = 100, which gives QR² = 36, and thus QR = 6.
Subtract 64 from both sides to isolate QR², then take the square root of 36.

Anahtar Kavram

Properties of rectangles and the application of the Pythagorean theorem to right triangles formed by diagonals.
Soru 2469Soru →

A circle in the standard (x,y)(x, y) coordinate plane is defined by the equation x2+y2−6x+4y−12=0x^2 + y^2 - 6x + 4y - 12 = 0. A line LL passes through the center of this circle and is perpendicular to the line with equation 3x−4y=123x - 4y = 12. What is the yy-coordinate of the intersection point of line LL and the circle that has a positive yy-value?

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Cevap: 2

Cevap

The y-coordinate of the intersection point with a positive y-value is 2.
Completing the square of the circle equation x2+y2−6x+4y−12=0x^2 + y^2 - 6x + 4y - 12 = 0 yields (x−3)2+(y+2)2=25(x-3)^2 + (y+2)^2 = 25, giving center (3,−2)(3, -2) and radius r=5r = 5. The given line 3x−4y=123x - 4y = 12 has a slope of 3/43/4, so a perpendicular line LL has a slope of −4/3-4/3. Since line LL passes through the center (3,−2)(3, -2) and has a slope of −4/3-4/3, moving a distance of 5 units along this line (which corresponds to a horizontal change of ±3\pm 3 and vertical change of ∓4\mp 4) gives the intersection points (6,−6)(6, -6) and (0,2)(0, 2). The y-coordinate of the point with a positive y-value is 2.

Adım Adım Çözüm

1
Complete the square for the circle's equation to find its center and radius.
The equation is rewritten as (x−3)2+(y+2)2=25(x-3)^2 + (y+2)^2 = 25, which represents a circle with center (3,−2)(3, -2) and radius r=5r = 5.
Converting to standard form (x−h)2+(y−k)2=r2(x-h)^2 + (y-k)^2 = r^2 gives the circle's center and radius.
2
Find the slope of the given line 3x−4y=123x - 4y = 12 and determine the slope of the perpendicular line LL.
The slope of the given line is 3/43/4. The slope of line LL is the negative reciprocal: −4/3-4/3.
Perpendicular lines have slopes that are negative reciprocals.
3
Find the intersection points of line LL and the circle.
Since line LL passes through the center (3,−2)(3, -2) and has a slope of −4/3-4/3, points on the line at a distance of the radius r=5r=5 are found by moving 3 units horizontally and 4 units vertically. This yields the points (3+3,−2−4)=(6,−6)(3 + 3, -2 - 4) = (6, -6) and (3−3,−2+4)=(0,2)(3 - 3, -2 + 4) = (0, 2).
The intersection points lie exactly one radius away from the center along the line.
4
Identify the y-coordinate with a positive value.
Between the points (6,−6)(6, -6) and (0,2)(0, 2), the point with a positive y-value is (0,2)(0, 2), so the y-coordinate is 2.
The question specifies the intersection point must have a positive y-value.

Anahtar Kavram

Circle standard equations and perpendicular lines on the coordinate plane
Soru 2470Soru →

In △ABC\triangle ABC, the measure of exterior angle ∠ACD\angle ACD is 135∘135^\circ, where DD lies on the extension of side BCBC past CC. If the measure of interior angle ∠A\angle A is 25∘25^\circ greater than the measure of interior angle ∠B\angle B, what is the measure, in degrees, of ∠B\angle B?

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Cevap: 55

Cevap

55
According to the Exterior Angle Theorem, the measure of exterior angle ∠ACD\angle ACD is equal to the sum of the measures of its remote interior angles, ∠A\angle A and ∠B\angle B. This gives the equation m∠A+m∠B=135∘\text{m}\angle A + \text{m}\angle B = 135^\circ. Using the information that m∠A=m∠B+25∘\text{m}\angle A = \text{m}\angle B + 25^\circ, we substitute this expression into the equation to get (m∠B+25∘)+m∠B=135∘(\text{m}\angle B + 25^\circ) + \text{m}\angle B = 135^\circ. Simplifying this equation gives 2m∠B+25=1352\text{m}\angle B + 25 = 135, which simplifies to 2m∠B=1102\text{m}\angle B = 110, and dividing by 2 yields m∠B=55∘\text{m}\angle B = 55^\circ.

Adım Adım Çözüm

1
Apply the Exterior Angle Theorem to express the relation between the exterior angle and the two remote interior angles.
m∠A+m∠B=135∘\text{m}\angle A + \text{m}\angle B = 135^\circ
The measure of an exterior angle of a triangle is equal to the sum of the measures of its two remote interior angles.
2
Substitute the relationship between the interior angles into the equation.
(m∠B+25∘)+m∠B=135∘(\text{m}\angle B + 25^\circ) + \text{m}\angle B = 135^\circ
The problem states that the measure of interior angle ∠A\angle A is 25∘25^\circ greater than the measure of interior angle ∠B\angle B.
3
Solve the algebraic equation for the measure of interior angle ∠B\angle B.
m∠B=55∘\text{m}\angle B = 55^\circ
Combining like terms gives 2m∠B+25=1352\text{m}\angle B + 25 = 135. Subtracting 25 from both sides gives 2m∠B=1102\text{m}\angle B = 110. Dividing by 2 yields m∠B=55∘\text{m}\angle B = 55^\circ.

Anahtar Kavram

Exterior Angle Theorem and remote interior angles relation
Soru 2471Soru →

A convex polygon has nn sides. The sum of the measures of its interior angles is 33 times the sum of the measures of its exterior angles. What is the value of nn?

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Cevap: 8

Cevap

8
The sum of the interior angle measures of an nn-sided convex polygon is (n−2)×180∘(n-2) \times 180^\circ. The sum of the exterior angle measures is always 360∘360^\circ. According to the problem, the sum of the interior angles is 33 times the sum of the exterior angles, which can be written as the equation (n−2)×180=3×360(n-2) \times 180 = 3 \times 360. Simplifying the right side gives (n−2)×180=1080(n-2) \times 180 = 1080. Dividing both sides by 180180 results in n−2=6n - 2 = 6. Adding 22 to both sides yields n=8n = 8.

Adım Adım Çözüm

1
Use the formula for the sum of the interior angle measures of a convex polygon with nn sides.
The sum of the interior angles is (n−2)×180∘(n-2) \times 180^\circ.
By the polygon interior angle sum theorem, the sum of the interior angles of any convex nn-gon is (n−2)×180∘(n-2) \times 180^\circ.
2
Identify the sum of the exterior angle measures of a convex polygon.
The sum of the exterior angles is 360∘360^\circ.
The sum of the exterior angles of any convex polygon is always constant and equals 360∘360^\circ, regardless of the number of sides.
3
Set up the equation relating the two sums as given in the problem statement.
(n−2)×180∘=3×360∘(n-2) \times 180^\circ = 3 \times 360^\circ
The problem states that the sum of the interior angles is 33 times the sum of the exterior angles.
4
Solve the equation for nn.
n=8n = 8
Divide both sides by 180∘180^\circ to get n−2=6n - 2 = 6, then add 22 to both sides to find n=8n = 8.

Anahtar Kavram

The sum of the interior angles of a convex polygon with nn sides is (n−2)×180∘(n-2) \times 180^\circ, and the sum of its exterior angles is 360∘360^\circ.
Soru 2472Soru →

The sum of the measures of the interior angles of a convex polygon is 900∘900^\circ. How many sides does this polygon have?

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Cevap: 7

Cevap

The polygon has 7 sides.
The correct answer is 77 because the sum of the interior angles of a convex polygon with nn sides is (n−2)×180∘(n - 2) \times 180^\circ. Setting this equal to 900∘900^\circ yields (n−2)×180=900(n - 2) \times 180 = 900. Dividing both sides by 180180 gives n−2=5n - 2 = 5, and adding 22 to both sides results in n=7n = 7.

Adım Adım Çözüm

1
Set up the equation for the sum of the interior angles of a polygon.
(n−2)×180∘=900∘(n - 2) \times 180^\circ = 900^\circ
The sum of the interior angles of a convex polygon with nn sides is always (n−2)×180∘(n - 2) \times 180^\circ.
2
Divide both sides of the equation by 180∘180^\circ.
n−2=5n - 2 = 5
To isolate the term with nn, we divide 900900 by 180180.
3
Solve for nn by adding 22 to both sides.
n=7n = 7
Adding 22 to both sides isolates the variable nn.

Anahtar Kavram

The sum of the interior angles of an nn-sided convex polygon is (n−2)×180∘(n - 2) \times 180^\circ.
Tahmini Süre:45s
Soru 2473Soru →

What is the greatest integer value of kk that satisfies the inequality 8−3(2k−5)≥4(k+6)8 - 3(2k - 5) \geq 4(k + 6)?

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Cevap: -1

Cevap

The greatest integer value of kk that satisfies the inequality is −1-1.
Solving the inequality step-by-step yields k≤−0.1k \leq -0.1. The greatest integer less than or equal to −0.1-0.1 is −1-1.

Adım Adım Çözüm

1
Distribute the coefficients to remove parentheses
8−6k+15≥4k+248 - 6k + 15 \geq 4k + 24
Expanding the terms makes it possible to combine like terms on each side of the inequality.
2
Combine like terms on the left side
23−6k≥4k+2423 - 6k \geq 4k + 24
Simplifying the constant values on the left side (8+15=238 + 15 = 23) simplifies the expression.
3
Subtract 4k4k from both sides
23−10k≥2423 - 10k \geq 24
This groups all the variable terms on the left-hand side.
4
Subtract 2323 from both sides
−10k≥1-10k \geq 1
This isolates the variable term on the left-hand side.
5
Divide by −10-10 and flip the inequality sign
k≤−0.1k \leq -0.1
Dividing both sides by a negative number requires reversing the direction of the inequality sign.
6
Identify the greatest integer satisfying the inequality
k=−1k = -1
The largest integer that is less than or equal to −0.1-0.1 is −1-1.

Anahtar Kavram

Solving linear inequalities and applying the sign-flip rule when dividing by a negative number.
Tahmini Süre:1m 30s
Soru 2474Soru →

A triangle has two sides of length 99 and 1414. The length of the third side, ss, is a multiple of 44. What is the sum of all possible integer values for ss?

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Cevap: 56

Cevap

56
According to the Triangle Inequality Theorem, the length of the third side, ss, of a triangle with sides of length 9 and 14 must satisfy the inequality 14−9<s<14+914 - 9 < s < 14 + 9, which simplifies to 5<s<235 < s < 23. The integer values within this range that are multiples of 4 are 8, 12, 16, and 20. Adding these values together yields a sum of 56.

Adım Adım Çözüm

1
Apply the Triangle Inequality Theorem to determine the range of possible lengths for the third side.
The third side length, ss, must satisfy the inequality: 14−9<s<14+914 - 9 < s < 14 + 9, which simplifies to 5<s<235 < s < 23.
The Triangle Inequality Theorem states that the length of any side of a triangle must be strictly greater than the positive difference of the other two sides and strictly less than the sum of the other two sides.
2
Identify all integer values in the range (5,23)(5, 23) that are multiples of 4.
The multiples of 4 that are strictly greater than 5 and strictly less than 23 are: 8, 12, 16, and 20.
We must find the integers within the bounds that can be divided by 4 with a remainder of 0.
3
Calculate the sum of the identified multiples of 4.
8+12+16+20=568 + 12 + 16 + 20 = 56.
The question asks for the sum of all possible integer values for the third side length ss.

Anahtar Kavram

Triangle Inequality Theorem
Tahmini Süre:1m 0s
Soru 2475Soru →

A regular decagon has 1010 sides of equal length. What is the measure, in degrees, of one exterior angle of this decagon?

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Cevap: 36

Cevap

The correct answer is 36.
The sum of the exterior angles of any convex polygon is always 360∘360^\circ. A regular decagon has 1010 congruent sides and therefore 1010 congruent exterior angles. Dividing 360∘360^\circ by 1010 yields 36∘36^\circ for each exterior angle.

Adım Adım Çözüm

1
Determine the number of exterior angles in a regular decagon.
A decagon has 10 sides, so it has 10 exterior angles.
A polygon has the same number of exterior angles as its number of sides.
2
State the sum of the exterior angles for a convex polygon.
The sum of the exterior angles is 360 degrees.
The exterior angles of any convex polygon always sum to 360 degrees regardless of the number of sides.
3
Calculate the measure of one exterior angle.
360 / 10 = 36
Since the decagon is regular, all of its exterior angles are equal in measure, so we divide the total sum by the number of angles.

Anahtar Kavram

The sum of the exterior angles of any convex polygon is 360∘360^\circ. For a regular polygon with nn sides, the measure of each exterior angle is 360∘n\frac{360^\circ}{n}.
Soru 2476Soru →

The measures of the interior angles of a convex pentagon are in the ratio 2:3:4:4:52:3:4:4:5. What is the degree measure of the smallest interior angle in this pentagon?

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Cevap: 60∘60^\circ

Cevap

60∘60^\circ
The sum of the interior angles of a convex pentagon is calculated as (5−2)×180∘=540∘(5 - 2) \times 180^\circ = 540^\circ. Representing the five angle measures in the given ratio as 2x2x, 3x3x, 4x4x, 4x4x, and 5x5x, their sum is 18x=540∘18x = 540^\circ, which gives x=30∘x = 30^\circ. The smallest angle corresponds to the smallest term in the ratio, which is 2x=2×30∘=60∘2x = 2 \times 30^\circ = 60^\circ. Therefore, the correct measure is 60∘60^\circ.

Adım Adım Çözüm

1
Determine the sum of the interior angles of a convex pentagon.
The sum is (5−2)×180∘=3×180∘=540∘(5 - 2) \times 180^\circ = 3 \times 180^\circ = 540^\circ.
The sum of the interior angles of any convex nn-gon is given by the formula (n−2)×180∘(n - 2) \times 180^\circ, and a pentagon has 55 sides.
2
Set up an algebraic equation using the given ratio of the angle measures.
Let the angle measures be 2x2x, 3x3x, 4x4x, 4x4x, and 5x5x. Their sum is 2x+3x+4x+4x+5x=18x=540∘2x + 3x + 4x + 4x + 5x = 18x = 540^\circ.
The sum of the actual angle measures must equal the total interior angle sum of the pentagon.
3
Solve for the variable xx.
x=540∘/18=30∘x = 540^\circ / 18 = 30^\circ.
Dividing the total sum by the sum of the ratio parts gives the value of a single ratio unit.
4
Calculate the measure of the smallest interior angle.
Smallest angle =2x=2×30∘=60∘= 2x = 2 \times 30^\circ = 60^\circ.
The smallest term in the ratio is 22, so multiplying this term by xx gives the smallest angle measure.

Anahtar Kavram

The sum of the interior angles of a convex polygon with nn sides is (n−2)×180∘(n-2) \times 180^\circ. For an irregular polygon with angles in a given ratio, the individual angle measures can be found by setting up a linear equation where the sum of the ratio parts multiplied by a variable equals the total sum.
Soru 2477Soru →

A geometric sequence consists of positive terms and has a first term of 1212 and a common ratio of rr. An arithmetic sequence has a first term of 55 and a common difference of dd. If the 3rd3\text{rd} term of the geometric sequence is 33 and the 4th4\text{th} term of the arithmetic sequence is 77, what is the value of r+dr + d?

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Cevap: 76\frac{7}{6}

Cevap

76\frac{7}{6}
The correct value is 76\frac{7}{6}. This is found by first calculating the common ratio of the geometric sequence, where 12r2=3⇒r2=14⇒r=1212r^2 = 3 \Rightarrow r^2 = \frac{1}{4} \Rightarrow r = \frac{1}{2}, and the common difference of the arithmetic sequence, where 5+3d=7⇒3d=2⇒d=235 + 3d = 7 \Rightarrow 3d = 2 \Rightarrow d = \frac{2}{3}. Adding these two fractions with a common denominator yields 36+46=76\frac{3}{6} + \frac{4}{6} = \frac{7}{6}.

Adım Adım Çözüm

1
Find the common ratio rr of the geometric sequence.
r=12r = \frac{1}{2}
The formula for the nthn\text{th} term of a geometric sequence is gn=g1⋅rn−1g_n = g_1 \cdot r^{n-1}. For the 3rd3\text{rd} term, g3=12r2=3g_3 = 12r^2 = 3, which simplifies to r2=14r^2 = \frac{1}{4}. Since the sequence has positive terms, we take the positive square root to get r=12r = \frac{1}{2}.
2
Find the common difference dd of the arithmetic sequence.
d=23d = \frac{2}{3}
The formula for the nthn\text{th} term of an arithmetic sequence is an=a1+(n−1)da_n = a_1 + (n-1)d. For the 4th4\text{th} term, a4=5+3d=7a_4 = 5 + 3d = 7, which simplifies to 3d=23d = 2, or d=23d = \frac{2}{3}.
3
Calculate the sum of rr and dd.
r+d=76r + d = \frac{7}{6}
Adding the two values with a common denominator of 66 gives 12+23=36+46=76\frac{1}{2} + \frac{2}{3} = \frac{3}{6} + \frac{4}{6} = \frac{7}{6}.

Anahtar Kavram

Arithmetic and Geometric Sequences and Series
Tahmini Süre:1m 30s
Soru 2478Soru →

Is the following statement true or false? In any rectangle, the diagonals must be perpendicular to each other.

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Cevap: False

Cevap

False
The correct answer is False because the diagonals of a rectangle are perpendicular only when the rectangle has equal side lengths (making it a square). In a standard rectangle, the diagonals are congruent and bisect each other, but they do not intersect at right angles.

Adım Adım Çözüm

1
Analyze the properties of a general rectangle.
A rectangle is a parallelogram with four right angles. Its diagonals are congruent and bisect each other.
To determine diagonal behavior, we must start with the standard properties of the shape.
2
Examine if the diagonals are perpendicular in all cases.
The diagonals of a rectangle are perpendicular only if the rectangle is a square (all sides equal). For a general rectangle with unequal adjacent sides, the diagonals are not perpendicular.
A single counterexample, such as a rectangle with unequal adjacent sides, shows that the property does not hold universally.

Anahtar Kavram

Properties of rectangle diagonals
Tahmini Süre:45s
Soru 2479Soru →

In the standard (x,y)(x, y) coordinate plane, a circle is centered at the origin (0,0)(0,0) and has a radius of 88. A horizontal chord ABAB lies entirely in the first and second quadrants at a distance of 44 units from the xx-axis. A point PP is located on the circle such that △ABP\triangle ABP is a right triangle. If the hypotenuse of △ABP\triangle ABP is a diameter of the circle, what is the area of △ABP\triangle ABP?

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Cevap: 32332\sqrt{3}

Cevap

The area of the right triangle is 32332\sqrt{3}.
The correct answer is 32332\sqrt{3}. The horizontal chord ABAB has yy-coordinate 44, and its endpoints lie on the circle x2+y2=64x^2 + y^2 = 64. Solving for xx gives x=±43x = \pm 4\sqrt{3}, so the length of the chord is 838\sqrt{3}. Because the triangle is inscribed in the circle and is a right triangle, its hypotenuse must be a diameter of the circle (length 1616). Since AB<16AB < 16, ABAB is a leg, and the hypotenuse is one of the other sides (e.g., APAP). The remaining leg BPBP is found using the Pythagorean theorem: BP=162−(83)2=256−192=64=8BP = \sqrt{16^2 - (8\sqrt{3})^2} = \sqrt{256 - 192} = \sqrt{64} = 8. The area of the right triangle is 12×83×8=323\frac{1}{2} \times 8\sqrt{3} \times 8 = 32\sqrt{3}.

Adım Adım Çözüm

1
Determine the length of chord ABAB.
The length of chord ABAB is 838\sqrt{3}.
The equation of the circle is x2+y2=64x^2 + y^2 = 64. Since the chord is horizontal and at a distance of 44 units from the xx-axis, its yy-coordinate is 44. Substituting y=4y = 4 gives x2+16=64⇒x2=48⇒x=±43x^2 + 16 = 64 \Rightarrow x^2 = 48 \Rightarrow x = \pm 4\sqrt{3}. The distance between A(−43,4)A(-4\sqrt{3}, 4) and B(43,4)B(4\sqrt{3}, 4) is 838\sqrt{3}.
2
Apply the rule for a right triangle inscribed in a circle to identify the hypotenuse.
The hypotenuse must be a diameter of length 1616, so the right angle is at BB (or AA).
Any right triangle inscribed in a circle must have a diameter as its hypotenuse. The diameter of this circle is 2×8=162 \times 8 = 16. Since the chord AB=83≈13.86AB = 8\sqrt{3} \approx 13.86 is shorter than the diameter, it cannot be the hypotenuse. Therefore, either APAP or BPBP is the hypotenuse (a diameter), making the angle opposite to it (either ∠ABP\angle ABP or ∠BAP\angle BAP) the 90∘90^\circ angle.
3
Calculate the length of the remaining leg of the right triangle.
The length of leg BPBP is 88.
Using the Pythagorean theorem for right triangle ABPABP with hypotenuse AP=16AP = 16 and leg AB=83AB = 8\sqrt{3}: AB2+BP2=AP2⇒(83)2+BP2=162⇒192+BP2=256⇒BP2=64⇒BP=8AB^2 + BP^2 = AP^2 \Rightarrow (8\sqrt{3})^2 + BP^2 = 16^2 \Rightarrow 192 + BP^2 = 256 \Rightarrow BP^2 = 64 \Rightarrow BP = 8.
4
Compute the area of right triangle ABPABP.
The area is 32332\sqrt{3}.
The area of a right triangle is 12×base×height=12×AB×BP=12×83×8=323\frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times AB \times BP = \frac{1}{2} \times 8\sqrt{3} \times 8 = 32\sqrt{3}.

Anahtar Kavram

Applying the Pythagorean theorem and Thales's theorem (inscribed right triangles) to solve multi-step geometric problems on the coordinate plane.
Soru 2480Soru →

A business analyst models a company's weekly net profit, N(x)N(x), in dollars, as the difference between its weekly revenue, R(x)=(2x+5)(30−x)R(x) = (2x + 5)(30 - x), and its weekly production cost, C(x)=(x−4)2+150C(x) = (x - 4)^2 + 150, where xx represents the number of items sold. When N(x)N(x) is simplified and written in standard form as ax2+bx+cax^2 + bx + c, where aa, bb, and cc are integers, what is the value of the coefficient bb?

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Cevap: 63

Cevap

The coefficient bb is 6363.
Expanding the revenue polynomial gives R(x)=−2x2+55x+150R(x) = -2x^2 + 55x + 150 and the cost polynomial gives C(x)=x2−8x+166C(x) = x^2 - 8x + 166. Subtracting them gives N(x)=(−2x2+55x+150)−(x2−8x+166)=−3x2+63x−16N(x) = (-2x^2 + 55x + 150) - (x^2 - 8x + 166) = -3x^2 + 63x - 16. The coefficient of the xx term, which corresponds to bb, is 6363.

Adım Adım Çözüm

1
Expand the revenue expression R(x)=(2x+5)(30−x)R(x) = (2x + 5)(30 - x) using polynomial multiplication.
R(x)=−2x2+55x+150R(x) = -2x^2 + 55x + 150
To find the polynomial representing revenue in standard form.
2
Expand the cost expression C(x)=(x−4)2+150C(x) = (x - 4)^2 + 150 using binomial squaring.
C(x)=x2−8x+166C(x) = x^2 - 8x + 166
To find the polynomial representing cost in standard form.
3
Subtract the cost polynomial from the revenue polynomial: N(x)=R(x)−C(x)N(x) = R(x) - C(x), distributing the negative sign through all terms of the cost polynomial.
N(x)=−3x2+63x−16N(x) = -3x^2 + 63x - 16
To determine the net profit polynomial N(x)N(x) in standard form.
4
Identify the coefficient bb of the xx term in the standard form ax2+bx+cax^2 + bx + c.
b=63b = 63
To answer the specific question asking for the coefficient of the middle term.

Anahtar Kavram

Polynomial subtraction and expansion of algebraic expressions.
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