Tüm alıştırma soruları

5556 soru

Soru 2481Soru

A kite WXYZWXYZ has diagonals WYWY and XZXZ that intersect at point PP. If the length of WPWP is 44 centimeters, the length of PYPY is 99 centimeters, and the length of XPXP is 33 centimeters, what is the measure, in degrees, of angle WPXWPX?

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Cevap: 90

Cevap

90 degrees
The diagonals of a kite are always perpendicular to each other. Therefore, the angle formed at their intersection, angle WPXWPX, is a right angle, which measures exactly 9090 degrees. The given segment lengths are extra information.

Adım Adım Çözüm

1
Identify the fundamental property of the diagonals of a kite.
The diagonals of any kite are perpendicular to each other.
By geometric definition, the diagonals of a kite intersect at a right angle.
2
Determine the measure of the angle formed by the intersection of the diagonals.
Angle WPXWPX is a right angle, which measures exactly 9090 degrees.
Since the diagonals are perpendicular, their intersection forms four 9090-degree angles regardless of the lengths of the individual diagonal segments.

Anahtar Kavram

The diagonals of a kite are perpendicular (9090^\circ).
Soru 2482Soru

In the standard (x,y)(x, y) coordinate plane, a point PP is reflected across the yy-axis and then translated 4 units down and 3 units right. The coordinates of the resulting image point, PP', are (1,2)(1, -2). What are the coordinates of the original point PP?

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

Cevap

The coordinates of the original point PP are (2,2)(2, 2).
To find the coordinates of the original point P(x,y)P(x, y), we apply the inverse transformations in reverse order to the final image point P(1,2)P'(1, -2). First, we undo the translation of 4 units down and 3 units right by translating PP' 4 units up and 3 units left. This results in the intermediate coordinates (13,2+4)=(2,2)(1 - 3, -2 + 4) = (-2, 2). Next, we undo the reflection across the yy-axis by reflecting (2,2)(-2, 2) across the yy-axis again (since a reflection is its own inverse). Changing the sign of the xx-coordinate gives (2,2)(2, 2). Alternatively, setting up the equations x+3=1-x + 3 = 1 and y4=2y - 4 = -2 and solving them yields x=2x = 2 and y=2y = 2, which corresponds to the point (2,2)(2, 2).

Adım Adım Çözüm

1
Set up equations to express the composite transformations of the point P(x,y)P(x, y) to P(1,2)P'(1, -2).
Reflecting P(x,y)P(x, y) across the yy-axis changes the sign of the xx-coordinate, yielding (x,y)(-x, y). Translating this point 4 units down and 3 units right yields (x+3,y4)(-x + 3, y - 4).
Establishing the mathematical relationship for each transformation is necessary to work backward to find the coordinates of the pre-image.
2
Equate the coordinates of the transformed point to the coordinates of the final image point P(1,2)P'(1, -2).
x+3=1-x + 3 = 1 and y4=2y - 4 = -2
This sets up two independent linear equations that can be solved for the original coordinates xx and yy.
3
Solve the equations for xx and yy.
From x+3=1-x + 3 = 1, we get x=2-x = -2, which means x=2x = 2. From y4=2y - 4 = -2, we get y=2y = 2. Therefore, the coordinates of PP are (2,2)(2, 2).
Solving these equations gives the exact coordinates of the original pre-image point.

Anahtar Kavram

Working backward with composite transformations in the coordinate plane
Tahmini Süre:1m 15s
Soru 2483Soru

Elena Rostova stood on the damp deck of the research vessel, staring at the freshly extracted core sample from a white oak timber salvaged from the wreck of the Gryphon. The ship had foundered in the autumn of 1682, but the story written in its rings stretched much further back. Just last year, in 2025, Elena had published her thesis on the Little Ice Age, utilizing data she had gathered during her 2022 expedition to the Swedish archives. There, she had unearthed the ship’s original cargo manifest, which detailed the lumber's harvest in a Baltic forest during the exceptionally cold spring of 1679. Now, looking at the narrow rings under her magnifier, she traced the signature of a severe drought in 1665—a year before the Great Fire of London, which she recalled studying during her college years. This oak had weathered that dry summer as a young sapling, decades before it was felled by shipwrights to form the Gryphon's keel.

According to the passage, which of the following events occurred first chronologically?

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Cevap: The oak tree weathering a severe drought

Cevap

The oak tree weathering a severe drought
The oak tree weathering a severe drought is correct because the passage explicitly states this event occurred in 1665. This date precedes all other events mentioned in the text: the lumber harvest (1679), the sinking of the ship (1682), and Elena's research expedition (2022).

Adım Adım Çözüm

1
Identify the historical and modern dates linked to each event mentioned in the passage.
The drought occurred in 1665; the lumber harvest occurred in 1679; the Gryphon sank in 1682; and Elena's archival research occurred in 2022.
Extracting the specific dates for each event is the first step to establishing a correct chronological sequence.
2
Compare the dates to determine which occurred earliest in time.
The year 1665 is the earliest year among all the events described.
Finding the smallest numerical year value identifies the event that occurred first in the timeline.

Anahtar Kavram

Reconstructing a chronological timeline from a non-linear narrative by identifying and ordering events based on explicit dates and relative temporal clues.
Tahmini Süre:1m 30s
Soru 2484Soru

A triangle has a vertex at P(4,3)P(-4, 3) in the standard (x,y)(x, y) coordinate plane. If the triangle is reflected across the line y=xy = -x and then translated 33 units to the right and 44 units down, what are the coordinates of the image of vertex PP after both transformations?

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Cevap: (0,0)(0, 0)

Cevap

(0,0)(0, 0)
The coordinate (0,0)(0, 0) is correct because reflecting the point P(4,3)P(-4, 3) across the line y=xy = -x swaps and negates the coordinates, transforming it to (3,4)(-3, 4). Then, translating this point 33 units to the right and 44 units down is calculated as (3+3,44)(-3 + 3, 4 - 4), which simplifies to (0,0)(0, 0).

Adım Adım Çözüm

1
Apply the reflection across the line y=xy = -x to the coordinate P(4,3)P(-4, 3).
The rule for reflection across the line y=xy = -x is (x,y)(y,x)(x, y) \rightarrow (-y, -x). Applying this rule to P(4,3)P(-4, 3) yields (3,4)(-3, 4).
To find the coordinates of the vertex after the first transformation in the composite sequence.
2
Apply the translation of 33 units right and 44 units down to the intermediate point (3,4)(-3, 4).
Translating 33 units to the right adds 33 to the xx-coordinate, and translating 44 units down subtracts 44 from the yy-coordinate: (3+3,44)=(0,0)(-3 + 3, 4 - 4) = (0, 0).
To find the final position after the second transformation in the composite sequence.

Anahtar Kavram

Applying composite transformations in the coordinate plane, specifically a reflection across the line y=xy = -x followed by a translation.
Soru 2485Soru

For what value of the constant cc does the quadratic equation x23x+c=0x^2 - 3x + c = 0 have two complex solutions with imaginary parts equal to ±2i\pm 2i?

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Cevap: 6.256.25

Cevap

The value of the constant cc is 6.256.25.
The correct answer is 6.256.25. Applying the quadratic formula to x23x+c=0x^2 - 3x + c = 0 gives solutions of the form 1.5±94c21.5 \pm \frac{\sqrt{9 - 4c}}{2}. Since these solutions are complex with imaginary parts equal to ±2i\pm 2i, the term under the radical must be negative, and the imaginary component is 94c2=2i\frac{\sqrt{9 - 4c}}{2} = 2i. Multiplying both sides by 22 gives 94c=4i\sqrt{9 - 4c} = 4i. Squaring both sides results in 94c=16i29 - 4c = 16i^2. Substituting i2=1i^2 = -1 gives 94c=169 - 4c = -16. Solving for cc yields 4c=25-4c = -25, which simplifies to c=6.25c = 6.25.

Adım Adım Çözüm

1
Apply the quadratic formula to the equation x23x+c=0x^2 - 3x + c = 0.
The solutions are given by x=(3)±(3)24(1)(c)2(1)=1.5±94c2x = \frac{-(-3) \pm \sqrt{(-3)^2 - 4(1)(c)}}{2(1)} = 1.5 \pm \frac{\sqrt{9 - 4c}}{2}.
This expresses the solutions in terms of the constant cc so that the imaginary part can be identified.
2
Set the imaginary term of the solutions equal to the given imaginary parts ±2i\pm 2i.
94c2=2i    94c=4i\frac{\sqrt{9 - 4c}}{2} = 2i \implies \sqrt{9 - 4c} = 4i.
The question specifies that the imaginary parts of the two complex solutions are ±2i\pm 2i.
3
Square both sides of the equation to solve for cc.
94c=(4i)2=16i29 - 4c = (4i)^2 = 16i^2. Since i2=1i^2 = -1, this becomes 94c=169 - 4c = -16.
Squaring eliminates the radical and allows for standard algebraic isolation of the variable cc.
4
Solve the linear equation for cc.
4c=25    c=6.25-4c = -25 \implies c = 6.25.
Subtracting 99 from both sides and then dividing by 4-4 isolates the constant cc.

Anahtar Kavram

Solving quadratic equations with complex roots using the quadratic formula and the properties of the imaginary unit.
Soru 2486Soru

A sequence of numbers t1,t2,t3,t_1, t_2, t_3, \dots is defined by t1=3t_1 = 3 and tn+1=3tn2nt_{n+1} = 3t_n - 2^n for all integers n1n \geq 1. What is the value of the fourth term, t4t_4?

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Cevap: 43

Cevap

The value of the fourth term is 43.
To find t4t_4, we use the recursive formula tn+1=3tn2nt_{n+1} = 3t_n - 2^n. Substituting n=1n=1 gives t2=3(3)2=7t_2 = 3(3) - 2 = 7. Substituting n=2n=2 gives t3=3(7)4=17t_3 = 3(7) - 4 = 17. Substituting n=3n=3 gives t4=3(17)8=43t_4 = 3(17) - 8 = 43.

Adım Adım Çözüm

1
Calculate the second term, t2t_2, by substituting n=1n = 1 and t1=3t_1 = 3 into the formula tn+1=3tn2nt_{n+1} = 3t_n - 2^n.
t2=3t121=3(3)2=7t_2 = 3t_1 - 2^1 = 3(3) - 2 = 7
To progress to the fourth term, we must first find each preceding term in the sequence.
2
Calculate the third term, t3t_3, by substituting n=2n = 2 and t2=7t_2 = 7 into the formula.
t3=3t222=3(7)4=17t_3 = 3t_2 - 2^2 = 3(7) - 4 = 17
Using the value of the second term allows us to find the third term.
3
Calculate the fourth term, t4t_4, by substituting n=3n = 3 and t3=17t_3 = 17 into the formula.
t4=3t323=3(17)8=43t_4 = 3t_3 - 2^3 = 3(17) - 8 = 43
This completes the recursive process to find the target term.

Anahtar Kavram

Evaluating terms of a sequence defined by a recursive formula.
Tahmini Süre:1m 30s
Soru 2487Soru

A laboratory chamber's initial temperature is 72\frac{7}{2} degrees Celsius, and it decreases at a constant rate of 54\frac{5}{4} degrees Celsius per hour. The temperature of the chamber must reach at most 12-\frac{1}{2} degrees Celsius to complete an experiment. Which of the following inequalities represents the number of hours, hh, the experiment must run to reach this temperature?

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Cevap: h165h \geq \frac{16}{5}

Cevap

h165h \geq \frac{16}{5}
The correct answer is the inequality stating that hh must be greater than or equal to sixteen-fifths. This is found by setting up the linear inequality 7254h12\frac{7}{2} - \frac{5}{4}h \leq -\frac{1}{2}, subtracting 72\frac{7}{2} from both sides to get 54h4-\frac{5}{4}h \leq -4, and then multiplying by 45-\frac{4}{5} while reversing the inequality sign.

Adım Adım Çözüm

1
Set up the inequality representing the temperature constraint.
7254h12\frac{7}{2} - \frac{5}{4}h \leq -\frac{1}{2}
The initial temperature is 72\frac{7}{2}, the rate of decrease is 54\frac{5}{4} per hour hh, and the final temperature must be at most 12-\frac{1}{2}.
2
Subtract 72\frac{7}{2} from both sides of the inequality.
54h4-\frac{5}{4}h \leq -4
This isolates the variable term on the left side of the inequality. The subtraction is 1272=82=4-\frac{1}{2} - \frac{7}{2} = -\frac{8}{2} = -4.
3
Multiply both sides by 45-\frac{4}{5} and reverse the inequality sign.
h165h \geq \frac{16}{5}
Multiplying or dividing by a negative number requires reversing the direction of the inequality sign. The calculation is 4×(45)=165-4 \times \left(-\frac{4}{5}\right) = \frac{16}{5}.

Anahtar Kavram

Solving linear inequalities involving negative coefficients and applying the inequality sign-flip rule.
Tahmini Süre:1m 30s
Soru 2488Soru

In the standard (x,y)(x, y) coordinate plane, line TT is perpendicular to the line with the equation y=3x5y = 3x - 5. If line TT passes through the point (6,2)(6, 2), what is the yy-intercept of line TT?

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Cevap: 4

Cevap

The correct answer is 4
The slope of the line given by the equation y=3x5y = 3x - 5 is 33. Since line TT is perpendicular to this line, its slope must be the negative reciprocal of 33, which is 13-\frac{1}{3}. Using the point-slope form with the point (6,2)(6, 2), the equation of line TT is y2=13(x6)y - 2 = -\frac{1}{3}(x - 6). To find the yy-intercept of line TT, we set x=0x = 0 and solve for yy: y2=13(06)    y2=2    y=4y - 2 = -\frac{1}{3}(0 - 6) \implies y - 2 = 2 \implies y = 4.

Adım Adım Çözüm

1
Identify the slope of the given line from its equation.
The slope of the line y=3x5y = 3x - 5 is 33.
The equation is in slope-intercept form (y=mx+by = mx + b), where mm is the slope.
2
Determine the slope of the perpendicular line TT.
The slope of line TT is 13-\frac{1}{3}.
Perpendicular lines have slopes that are negative reciprocals of each other.
3
Use the point-slope form to write the equation of line TT with the point (6,2)(6, 2).
The equation of line TT is y2=13(x6)y - 2 = -\frac{1}{3}(x - 6).
The point-slope form is yy1=m(xx1)y - y_1 = m(x - x_1) where (x1,y1)(x_1, y_1) is a point on the line and mm is the slope.
4
Find the yy-intercept of line TT by setting x=0x = 0.
y=4y = 4.
The yy-intercept is the value of yy where the line crosses the yy-axis (when x=0x = 0).

Anahtar Kavram

Finding the equation and y-intercept of a perpendicular line using negative reciprocal slopes
Soru 2489Soru

In the standard (x,y)(x, y) coordinate plane, the midpoint of the line segment with endpoints A(1,3)A(1, 3) and B(7,x2)B\left(7, \frac{x}{2}\right) is MM. If the distance from the origin (0,0)(0, 0) to MM is 894\sqrt{\frac{89}{4}} units, and xx is a positive number, what is the value of xx?

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Cevap: 4

Cevap

The correct value of xx is 44.
The midpoint MM of A(1,3)A(1, 3) and B(7,x2)B\left(7, \frac{x}{2}\right) has coordinates (1+72,3+x22)=(4,x+64)\left(\frac{1+7}{2}, \frac{3 + \frac{x}{2}}{2}\right) = \left(4, \frac{x+6}{4}\right). The distance from (0,0)(0, 0) to MM is 42+(x+64)2=894\sqrt{4^2 + \left(\frac{x+6}{4}\right)^2} = \sqrt{\frac{89}{4}}. Squaring both sides yields 16+(x+6)216=89416 + \frac{(x+6)^2}{16} = \frac{89}{4}. Multiplying through by 16 gives 256+(x+6)2=356256 + (x+6)^2 = 356, which simplifies to (x+6)2=100(x+6)^2 = 100. Taking the square root of both sides gives x+6=10x+6 = 10 (since xx is positive), which simplifies to x=4x = 4.

Adım Adım Çözüm

1
Find the coordinates of the midpoint M(xM,yM)M(x_M, y_M) of the segment ABAB.
M=(4,x+64)M = \left(4, \frac{x+6}{4}\right)
By the midpoint formula, xM=1+72=4x_M = \frac{1 + 7}{2} = 4 and yM=3+x22=6+x22=x+64y_M = \frac{3 + \frac{x}{2}}{2} = \frac{\frac{6+x}{2}}{2} = \frac{x+6}{4}.
2
Set up the distance equation from the origin (0,0)(0, 0) to M(4,x+64)M\left(4, \frac{x+6}{4}\right) using the distance formula.
42+(x+64)2=894\sqrt{4^2 + \left(\frac{x+6}{4}\right)^2} = \sqrt{\frac{89}{4}}
The distance between the origin (0,0)(0, 0) and any point (x,y)(x, y) is given by d=x2+y2d = \sqrt{x^2 + y^2}.
3
Solve the distance equation for the positive variable xx.
x=4x = 4
Squaring both sides gives 16+(x+6)216=89416 + \frac{(x+6)^2}{16} = \frac{89}{4}. Multiplying by 16 yields 256+(x+6)2=356256 + (x+6)^2 = 356, which simplifies to (x+6)2=100(x+6)^2 = 100. Since xx is positive, x+6=10    x=4x+6 = 10 \implies x = 4.

Anahtar Kavram

Solving coordinate geometry problems by combining the midpoint formula and the distance formula.
Soru 2490Soru

An irregular convex polygon has nn sides. The measures of its interior angles, in degrees, are all distinct integers. If all of the interior angles are obtuse, what is the maximum possible value of nn?

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Cevap: 26

Cevap

The maximum possible value of nn is 26.
For a convex 2626-gon, the sum of the interior angles is 24×180=432024 \times 180^\circ = 4320^\circ. We can choose 2626 distinct integer angles from the range [91,179][91^\circ, 179^\circ] that sum to exactly 43204320^\circ because the maximum possible sum of 2626 distinct integers in this range is 43294329^\circ, which is greater than 43204320^\circ. For n=27n = 27, the sum of the interior angles must be 25×180=450025 \times 180^\circ = 4500^\circ, but the maximum possible sum of 2727 distinct integers in the range is only 44824482^\circ, which is less than 45004500^\circ. Therefore, 2626 is the maximum value of nn.

Adım Adım Çözüm

1
Determine the set of possible angle measures.
The angles must be integers in the range [91,179][91^\circ, 179^\circ].
Interior angles of a convex polygon must be less than 180180^\circ. Since they are obtuse and distinct integers, they must be strictly greater than 9090^\circ, giving the range [91,179][91, 179].
2
Write the sum of the interior angles of a convex nn-gon.
Sum =(n2)×180= (n - 2) \times 180^\circ.
This is the standard formula for the sum of the interior angles of any convex nn-gon.
3
Find the maximum possible sum of nn distinct angles in the range [91,179][91, 179].
Maximum Sum =179nn(n1)2= 179n - \frac{n(n - 1)}{2}.
The maximum sum is achieved by selecting the largest nn integers from the set: 179,178,,179(n1)179, 178, \dots, 179 - (n - 1).
4
Set up the inequality and simplify.
n2+n7200n^2 + n - 720 \le 0.
Since the sum of the angles must be less than or equal to the maximum possible sum, we have (n2)×180179nn(n1)2(n-2) \times 180 \le 179n - \frac{n(n-1)}{2}. Multiplying by 2 and simplifying yields the quadratic inequality.
5
Solve the quadratic inequality for the largest integer nn.
n=26n = 26.
Evaluating the quadratic expression for consecutive integers: for n=26n = 26, 262+26720=18026^2 + 26 - 720 = -18 \le 0; for n=27n = 27, 272+27720=36>027^2 + 27 - 720 = 36 > 0. Thus, 26 is the maximum possible integer value.

Anahtar Kavram

Sum of interior angles of a convex polygon combined with algebraic optimization.
Soru 2491Soru

If the diagonals of a convex quadrilateral divide the quadrilateral into four triangles of equal perimeter, then the quadrilateral must be a square. Is this statement true or false?

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Cevap: False

Cevap

The statement is false because any non-square rhombus satisfies the condition of being divided into four triangles of equal perimeter, yet it is not a square.
The correct answer is false because the equal-perimeter condition only requires the quadrilateral to be a rhombus (having four equal sides), but does not require the interior angles to be 90 degrees. Any non-square rhombus is a valid counterexample.

Adım Adım Çözüm

1
Analyze the given condition of equal perimeters for the four triangles formed by the diagonals of a convex quadrilateral.
The diagonals of any rhombus are perpendicular and bisect each other, dividing the rhombus into four congruent right triangles.
Congruent triangles have identical side lengths, meaning their perimeters are equal. Thus, every rhombus satisfies this property.
2
Determine if all quadrilaterals satisfying this property must be squares.
A square is a regular quadrilateral, meaning it must have both equal side lengths and interior angles of 90 degrees.
To verify if the statement is true, we must test if a non-square rhombus can satisfy the condition.
3
Construct a counterexample using a specific non-square rhombus.
Consider a rhombus with side lengths of 5 units and diagonals of lengths 6 units and 8 units. The diagonals divide it into four right triangles with sides 3, 4, and 5 units. Each triangle has a perimeter of 12 units.
This rhombus has equal perimeters for all four triangles, but its interior angles are not 90 degrees, proving it is not a square.

Anahtar Kavram

The relationship between the diagonals and side properties of rhombuses and squares.
Soru 2492Soru

A convex polygon has nn sides. The sum of the measures of its interior angles is 66 times the sum of the measures of its exterior angles (one at each vertex). What is the value of nn?

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Cevap: 14

Cevap

The number of sides, nn, of the convex polygon is 14.
The sum of the interior angles of a convex polygon with nn sides is given by the formula (n2)×180(n-2) \times 180^\circ, and the sum of its exterior angles is always 360360^\circ. According to the problem, the sum of the interior angles is 66 times the sum of the exterior angles, yielding the equation (n2)×180=6×360(n - 2) \times 180 = 6 \times 360. Dividing both sides of the equation by 180180 gives n2=12n - 2 = 12. Adding 22 to both sides results in n=14n = 14.

Adım Adım Çözüm

1
State the sum of interior and exterior angles formulas.
Interior sum = (n2)×180(n-2) \times 180^\circ, Exterior sum = 360360^\circ.
To represent the geometric properties of the polygon algebraically.
2
Set up the equation based on the given ratio.
(n2)×180=6×360(n-2) \times 180 = 6 \times 360.
The problem states the interior sum is 6 times the exterior sum.
3
Solve the equation for nn.
n=14n = 14.
Divide by 180 to get n2=12n - 2 = 12, then add 2 to both sides.

Anahtar Kavram

The sum of the interior angles of an nn-sided convex polygon is (n2)×180(n-2) \times 180^\circ, and the sum of the exterior angles (one per vertex) is always 360360^\circ.
Soru 2493Soru

In the quadratic equation 2x211x+c=02x^2 - 11x + c = 0, where cc is a constant, the ratio of the two real solutions is 3:83:8. What is the value of cc?

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Cevap: 12

Cevap

The value of the constant cc is 1212.
The correct answer is 1212. By representing the roots in the ratio of 3:83:8 as 3r3r and 8r8r, Vieta's formula for the sum of roots (ba-\frac{b}{a}) gives 3r+8r=112    11r=5.5    r=0.53r + 8r = -\frac{-11}{2} \implies 11r = 5.5 \implies r = 0.5. The actual roots are therefore 1.51.5 and 44. Using Vieta's formula for the product of roots (ca\frac{c}{a}) gives (1.5)(4)=c2    6=c2    c=12(1.5)(4) = \frac{c}{2} \implies 6 = \frac{c}{2} \implies c = 12.

Adım Adım Çözüm

1
Represent the roots using the given ratio.
Let the two roots of the quadratic equation be 3r3r and 8r8r.
The ratio of the two solutions is specified as 3:83:8.
2
Apply Vieta's formula for the sum of roots to find the ratio multiplier rr.
3r+8r=112    11r=5.5    r=0.53r + 8r = -\frac{-11}{2} \implies 11r = 5.5 \implies r = 0.5.
For a quadratic equation ax2+bx+c=0ax^2 + bx + c = 0, the sum of the roots is given by ba-\frac{b}{a}.
3
Determine the numerical values of the two roots.
The roots are 3(0.5)=1.53(0.5) = 1.5 and 8(0.5)=48(0.5) = 4.
Substitute the value of r=0.5r = 0.5 back into the expressions for the roots.
4
Apply Vieta's formula for the product of roots to solve for the constant cc.
(1.5)(4)=c2    6=c2    c=12(1.5)(4) = \frac{c}{2} \implies 6 = \frac{c}{2} \implies c = 12.
For a quadratic equation ax2+bx+c=0ax^2 + bx + c = 0, the product of the roots is given by ca\frac{c}{a}.

Anahtar Kavram

Vieta's formulas and the relationship between the roots and coefficients of a quadratic equation

Alternatif Yöntem

Alternatively, you can express the roots using the quadratic formula: x=11±1218c4x = \frac{11 \pm \sqrt{121 - 8c}}{4}. Since the ratio of the smaller root to the larger root is 3:83:8, we set up the equation: 111218c11+1218c=38\frac{11 - \sqrt{121 - 8c}}{11 + \sqrt{121 - 8c}} = \frac{3}{8}. Cross-multiplying gives 8(111218c)=3(11+1218c)    8881218c=33+31218c    55=111218c    5=1218c    25=1218c    8c=96    c=128(11 - \sqrt{121 - 8c}) = 3(11 + \sqrt{121 - 8c}) \implies 88 - 8\sqrt{121 - 8c} = 33 + 3\sqrt{121 - 8c} \implies 55 = 11\sqrt{121 - 8c} \implies 5 = \sqrt{121 - 8c} \implies 25 = 121 - 8c \implies 8c = 96 \implies c = 12.
Tahmini Süre:1m 30s
Soru 2494Soru

For all real values of xx that satisfy the inequality 53x24x+625 - \frac{3x - 2}{4} \ge \frac{x + 6}{2}, the solution set is represented by xbx \le b. What is the value of bb?

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Cevap: 2

Cevap

The value of bb is 2.
To solve 53x24x+625 - \frac{3x - 2}{4} \ge \frac{x + 6}{2}, multiply all terms by 4 to clear the denominators, resulting in 20(3x2)2(x+6)20 - (3x - 2) \ge 2(x + 6). Carefully distribute the negative sign to obtain 203x+22x+1220 - 3x + 2 \ge 2x + 12. Simplifying the left side gives 223x2x+1222 - 3x \ge 2x + 12. Moving the variable terms to one side yields 105x10 \ge 5x, which simplifies to x2x \le 2. Thus, the upper bound value bb is 2.

Adım Adım Çözüm

1
Multiply both sides of the inequality by the least common denominator, which is 4.
20(3x2)2(x+6)20 - (3x - 2) \ge 2(x + 6)
Multiplying all terms by the common denominator eliminates fractions and simplifies the inequality.
2
Distribute the negative sign to the numerator terms on the left and distribute the 2 on the right.
203x+22x+1220 - 3x + 2 \ge 2x + 12
Distributing the negative sign across (3x2)(3x - 2) changes it to 3x+2-3x + 2. Distributing 2 across (x+6)(x + 6) yields 2x+122x + 12.
3
Combine like terms on the left side of the inequality.
223x2x+1222 - 3x \ge 2x + 12
Combining the constant terms 2020 and 22 simplifies the expression to 2222.
4
Isolate the variable terms by adding 3x3x and subtracting 12 from both sides.
105x10 \ge 5x
Grouping variables on one side and constants on the other allows us to solve for xx.
5
Divide both sides by 5.
2x2 \ge x (or x2x \le 2)
Dividing by a positive number isolates the variable without changing the direction of the inequality sign.

Anahtar Kavram

Solving linear inequalities involving fractions and distributing negative coefficients.

Alternatif Yöntem

We can write the inequality by separating each fraction term first: 534x+2412x+625 - \frac{3}{4}x + \frac{2}{4} \ge \frac{1}{2}x + \frac{6}{2}. This simplifies to 5.50.75x0.5x+35.5 - 0.75x \ge 0.5x + 3. Subtracting 0.5x0.5x and 5.55.5 from both sides gives 1.25x2.5-1.25x \ge -2.5. Dividing by 1.25-1.25 and reversing the inequality sign gives x2x \le 2.
Tahmini Süre:1m 30s
Soru 2495Soru

An irregular convex hexagon has two interior angles measuring 9090^\circ and 130130^\circ, respectively. The remaining four interior angles have measures in the ratio 5:6:7:75:6:7:7. What is the degree measure of the largest interior angle in this hexagon?

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Cevap: 140140^\circ

Cevap

The correct answer is 140140^\circ.
The sum of the interior angles of a hexagon is 720720^\circ. Subtracting the two given angles (9090^\circ and 130130^\circ) leaves 500500^\circ for the remaining four angles. Since these angles are in the ratio 5:6:7:75:6:7:7, we represent them as 5x5x, 6x6x, 7x7x, and 7x7x. Their sum is 25x=50025x = 500^\circ, which gives x=20x = 20^\circ. The largest of the remaining angles is 7x=7(20)=1407x = 7(20^\circ) = 140^\circ. Since 140140^\circ is greater than both 9090^\circ and 130130^\circ, it is the largest interior angle of the hexagon.

Adım Adım Çözüm

1
Calculate the sum of the interior angles of a hexagon.
Using the formula for the sum of the interior angles of a polygon with nn sides, (n2)×180(n - 2) \times 180^\circ, for a hexagon (n=6n = 6), the sum is (62)×180=4×180=720(6 - 2) \times 180^\circ = 4 \times 180^\circ = 720^\circ.
To establish the total sum of all interior angles of the polygon.
2
Subtract the two known angle measures from the total sum.
72090130=500720^\circ - 90^\circ - 130^\circ = 500^\circ.
To find the sum of the remaining four interior angles.
3
Set up an algebraic equation to find the value of one ratio unit, xx.
5x+6x+7x+7x=500    25x=500    x=205x + 6x + 7x + 7x = 500^\circ \implies 25x = 500^\circ \implies x = 20^\circ.
To determine the constant multiplier for the ratio of the remaining angles.
4
Calculate the measures of the remaining angles and determine the largest angle.
The remaining angles are 5(20)=1005(20^\circ) = 100^\circ, 6(20)=1206(20^\circ) = 120^\circ, 7(20)=1407(20^\circ) = 140^\circ, and 7(20)=1407(20^\circ) = 140^\circ. Comparing all six angles of the hexagon (90,100,120,130,140,14090^\circ, 100^\circ, 120^\circ, 130^\circ, 140^\circ, 140^\circ), the largest angle is 140140^\circ.
To identify the maximum interior angle measure of the hexagon.

Anahtar Kavram

The sum of the interior angles of a convex polygon with nn sides is (n2)×180(n - 2) \times 180^\circ. The individual angle measures in an irregular polygon can be determined using algebraic representations of their relationships or ratios.

Alternatif Yöntem

Once the value of the ratio unit x=20x = 20^\circ is determined, you can quickly find the largest candidate angle by multiplying the largest ratio component (77) by xx to get 7(20)=1407(20^\circ) = 140^\circ, and then compare it to the given angles (9090^\circ and 130130^\circ) to verify that it is indeed the largest.
Tahmini Süre:1m 30s
Soru 2496Soru

The ratio of the measure of an interior angle of a regular polygon to the measure of its exterior angle is 3:13:1. How many sides does this polygon have?

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Cevap: 8

Cevap

8
The interior angle and exterior angle of a polygon at any vertex are supplementary, meaning they add up to 180180^\circ. Given the ratio of the interior angle to the exterior angle is 3:13:1, we can express their measures as 3x3x and xx. Solving the equation 3x+x=1803x + x = 180^\circ gives 4x=1804x = 180^\circ, which means x=45x = 45^\circ. Therefore, the measure of each exterior angle of the regular polygon is 4545^\circ. Since the sum of the exterior angles of any convex polygon is always 360360^\circ, the number of sides nn is calculated by dividing 360360^\circ by the measure of one exterior angle: n=36045=8n = \frac{360^\circ}{45^\circ} = 8.

Adım Adım Çözüm

1
Set up an equation for the interior and exterior angles using the given ratio.
Let the measure of the exterior angle be xx and the measure of the interior angle be 3x3x.
The ratio of the interior angle to the exterior angle is 3:13:1, so their measures can be represented as 3x3x and xx respectively.
2
Use the fact that the interior angle and exterior angle at any vertex of a polygon are supplementary (form a linear pair).
3x+x=180    4x=180    x=453x + x = 180^\circ \implies 4x = 180^\circ \implies x = 45^\circ.
An interior angle and its adjacent exterior angle always lie on a straight line and sum to 180180^\circ.
3
Calculate the number of sides of the regular polygon using the measure of one exterior angle.
n=36045=8n = \frac{360^\circ}{45^\circ} = 8.
The sum of the exterior angles of any convex polygon is always 360360^\circ. For a regular polygon with nn sides, each exterior angle measures 360n\frac{360^\circ}{n}.

Anahtar Kavram

The relationship between the interior and exterior angles of a regular polygon, and the formula relating the number of sides to the sum of the exterior angles.
Soru 2497Soru

In the standard (x,y)(x, y) coordinate plane, a circle is defined by the equation x2+y2=25x^2 + y^2 = 25 and a line is defined by the equation 3x+4y=153x + 4y = 15. The line intersects the circle at two points, AA and BB. What is the distance between point AA and point BB?

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Cevap: 8

Cevap

The distance between the two intersection points is 8.
The correct answer is 8. We can find the intersection points by substituting y=153x4y = \frac{15 - 3x}{4} into the circle's equation x2+y2=25x^2 + y^2 = 25, yielding the quadratic equation 5x218x35=05x^2 - 18x - 35 = 0. Solving this gives x=5x = 5 and x=1.4x = -1.4, with corresponding yy-coordinates y=0y = 0 and y=4.8y = 4.8. The distance between (5,0)(5, 0) and (1.4,4.8)(-1.4, 4.8) is (1.45)2+(4.80)2=6.42+4.82=64=8\sqrt{(-1.4 - 5)^2 + (4.8 - 0)^2} = \sqrt{6.4^2 + 4.8^2} = \sqrt{64} = 8. Alternatively, we can use geometry: the distance from the center of the circle (0,0)(0,0) to the line 3x+4y15=03x + 4y - 15 = 0 is d=3(0)+4(0)1532+42=3d = \frac{|3(0) + 4(0) - 15|}{\sqrt{3^2 + 4^2}} = 3. Since the radius of the circle is r=5r = 5, the right triangle formed by the radius, the perpendicular segment, and half the chord has a half-chord length of 5232=4\sqrt{5^2 - 3^2} = 4. Thus, the total chord length is 2×4=82 \times 4 = 8.

Adım Adım Çözüm

1
Express the linear equation in terms of one variable
y=153x4y = \frac{15 - 3x}{4}
This allows for substitution into the equation of the circle.
2
Substitute the expression into the circle's equation and simplify
x2+(153x4)2=2516x2+(22590x+9x2)=40025x290x175=05x218x35=0x^2 + \left(\frac{15 - 3x}{4}\right)^2 = 25 \Rightarrow 16x^2 + (225 - 90x + 9x^2) = 400 \Rightarrow 25x^2 - 90x - 175 = 0 \Rightarrow 5x^2 - 18x - 35 = 0
To create a single quadratic equation in terms of xx representing the intersection points.
3
Solve the quadratic equation for xx
(5x+7)(x5)=0x=5(5x + 7)(x - 5) = 0 \Rightarrow x = 5 or x=1.4x = -1.4
To find the xx-coordinates of the intersection points.
4
Calculate the corresponding yy-coordinates
For x=5x = 5, y=0y = 0, giving point A(5,0)A(5, 0). For x=1.4x = -1.4, y=4.8y = 4.8, giving point B(1.4,4.8)B(-1.4, 4.8).
To determine the exact coordinates of both intersection points.
5
Apply the distance formula to find the length of the segment ABAB
d=(1.45)2+(4.80)2=(6.4)2+4.82=40.96+23.04=64=8d = \sqrt{(-1.4 - 5)^2 + (4.8 - 0)^2} = \sqrt{(-6.4)^2 + 4.8^2} = \sqrt{40.96 + 23.04} = \sqrt{64} = 8
To compute the final distance between the two intersection points.

Anahtar Kavram

Solving systems of linear and quadratic equations to determine intersection points and calculating the distance between coordinates.
Soru 2498Soru

A regular hexagon ABCDEFABCDEF has a side length of 88 inches. Point MM lies on side CDCD such that the length of segment CMCM is 22 inches. What is the length, in inches, of segment AMAM?

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Cevap: 14

Cevap

14
The correct answer is 14 because ACM\triangle ACM is a right triangle with legs AC=83AC = 8\sqrt{3} and CM=2CM = 2. Applying the Pythagorean Theorem yields AM2=(83)2+22=192+4=196AM^2 = (8\sqrt{3})^2 + 2^2 = 192 + 4 = 196, so AM=196=14AM = \sqrt{196} = 14.

Adım Adım Çözüm

1
Find the properties of the regular hexagon and the diagonal ACAC.
The interior angle at vertex BB is 120120^\circ. Since AB=BC=8AB = BC = 8, the triangle ABC\triangle ABC is an isosceles triangle with angles BAC=BCA=30\angle BAC = \angle BCA = 30^\circ. Using the properties of 3030^\circ-6060^\circ-9090^\circ triangles, the diagonal length is AC=83AC = 8\sqrt{3}.
To find the length of the leg ACAC for the right triangle ACM\triangle ACM.
2
Determine the angle ACD\angle ACD to show ACM\triangle ACM is a right triangle.
Since the interior angle BCD=120\angle BCD = 120^\circ and BCA=30\angle BCA = 30^\circ, the remaining angle is ACD=12030=90\angle ACD = 120^\circ - 30^\circ = 90^\circ. Thus, ACM\triangle ACM is a right triangle with the right angle at vertex CC.
To establish the right-angle relationship between the legs ACAC and CMCM.
3
Apply the Pythagorean Theorem to calculate the hypotenuse AMAM.
AM2=AC2+CM2=(83)2+22=192+4=196AM^2 = AC^2 + CM^2 = (8\sqrt{3})^2 + 2^2 = 192 + 4 = 196. Taking the square root gives AM=14AM = 14.
To find the final length of segment AMAM.

Anahtar Kavram

Using properties of regular hexagons, special right triangles, and the Pythagorean Theorem to find lengths in multi-step plane geometry configurations.
Soru 2499Soru

A homeowner has a square patio with a side length of 3x23x - 2 feet. She decides to cover a portion of the patio with a rectangular outdoor rug that has dimensions 2x12x - 1 feet by x+4x + 4 feet. Which of the following expressions represents the area, in square feet, of the patio that remains uncovered by the rug?

Cevabı ve açıklamayı göster

Cevap: 7x219x+87x^2 - 19x + 8

Cevap

7x219x+87x^2 - 19x + 8
The expression representing the uncovered area is obtained by subtracting the area of the rug from the area of the patio. First, the area of the square patio is calculated as (3x2)2=9x212x+4(3x - 2)^2 = 9x^2 - 12x + 4. Second, the area of the rug is calculated as (2x1)(x+4)=2x2+7x4(2x - 1)(x + 4) = 2x^2 + 7x - 4. Subtracting the rug's area from the patio's area requires distributing the negative sign: (9x212x+4)(2x2+7x4)=9x212x+42x27x+4(9x^2 - 12x + 4) - (2x^2 + 7x - 4) = 9x^2 - 12x + 4 - 2x^2 - 7x + 4. Combining like terms yields 7x219x+87x^2 - 19x + 8.

Adım Adım Çözüm

1
Calculate the area of the square patio by squaring its side length.
Apatio=(3x2)2=9x212x+4A_{\text{patio}} = (3x - 2)^2 = 9x^2 - 12x + 4
The area of a square is equal to the square of its side length: Area=s2\text{Area} = s^2.
2
Calculate the area of the rectangular rug by multiplying its length and width.
Arug=(2x1)(x+4)=2x2+8xx4=2x2+7x4A_{\text{rug}} = (2x - 1)(x + 4) = 2x^2 + 8x - x - 4 = 2x^2 + 7x - 4
The area of a rectangle is equal to the product of its length and width: Area=l×w\text{Area} = l \times w.
3
Subtract the area of the rug from the area of the patio, distributing the negative sign to all terms of the rug's area.
Auncovered=(9x212x+4)(2x2+7x4)=9x212x+42x27x+4=7x219x+8A_{\text{uncovered}} = (9x^2 - 12x + 4) - (2x^2 + 7x - 4) = 9x^2 - 12x + 4 - 2x^2 - 7x + 4 = 7x^2 - 19x + 8
Subtracting a polynomial requires distributing the negative sign to every term inside the parentheses and then combining like terms.

Anahtar Kavram

Subtracting one polynomial from another requires distributing the negative sign to every term of the subtracted polynomial before combining like terms.
Tahmini Süre:1m 30s
Soru 2500Soru

A triangle has side lengths of xx, 2x2x, and 1515, where xx is an integer. What is the total number of possible values for xx?

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Cevap: 9

Cevap

9
Applying the Triangle Inequality Theorem yields three inequalities: x+2x>15x + 2x > 15 (which simplifies to x>5x > 5), x+15>2xx + 15 > 2x (which simplifies to x<15x < 15), and 2x+15>x2x + 15 > x (which is always true since xx is positive). Combining these results in 5<x<155 < x < 15. The integers in this range are {6,7,8,9,10,11,12,13,14}\{6, 7, 8, 9, 10, 11, 12, 13, 14\}. Counting them gives 9 possible values.

Adım Adım Çözüm

1
Set up the three inequalities using the Triangle Inequality Theorem for the sides xx, 2x2x, and 1515.
The inequalities are x+2x>15x + 2x > 15, x+15>2xx + 15 > 2x, and 2x+15>x2x + 15 > x.
The sum of the lengths of any two sides of a triangle must be strictly greater than the length of the third side.
2
Solve each inequality for xx.
3x>15    x>53x > 15 \implies x > 5, and 15>x    x<1515 > x \implies x < 15. The third inequality x>15x > -15 is always true for positive side lengths.
To find the range of valid values for xx.
3
Combine the inequalities and count the possible integer values for xx.
The combined range is 5<x<155 < x < 15. The integer values are {6,7,8,9,10,11,12,13,14}\{6, 7, 8, 9, 10, 11, 12, 13, 14\}, which gives 146+1=914 - 6 + 1 = 9 values.
Since xx is specified as an integer, we must identify and count all integers strictly between 5 and 15.

Anahtar Kavram

Triangle Inequality Theorem

Alternatif Yöntem

Instead of algebraic manipulation, we can test values of xx directly. For x=5x=5, the sides are 5,10,155, 10, 15, but 5+10=155+10=15, which does not form a triangle. For x=15x=15, the sides are 15,30,1515, 30, 15, but 15+15=3015+15=30, which also does not form a triangle. Testing integer values between 55 and 1515 confirms they all satisfy the triangle inequality, resulting in 9 valid integers.
Tahmini Süre:1m 0s
ÖncekiSayfa 125 / 278Sonraki
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