Geometry

156 soru

Soru 101Soru

In a circle centered at point OO, the radius is 66 units and central angle POQ\angle POQ measures 120120^\circ. Which of the following statements regarding sector POQPOQ and minor arc PQPQ must be true? Select all such statements.

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Cevap: The length of minor arc PQPQ is 4π4\pi units.; The area of sector POQPOQ is 12π12\pi square units.

Cevap

The correct statements are that the length of minor arc PQPQ is 4π4\pi units and the area of sector POQPOQ is 12π12\pi square units.
The correct statements accurately apply the arc length and sector area formulas by multiplying the full circumference (12π12\pi) and full area (36π36\pi) by the central angle fraction 120360=13\frac{120^\circ}{360^\circ} = \frac{1}{3}, yielding an arc length of 4π4\pi units and a sector area of 12π12\pi square units.

Adım Adım Çözüm

1
Calculate the central angle fraction of the circle.
The fraction of the circle represented by sector POQPOQ is 120360=13\frac{120^\circ}{360^\circ} = \frac{1}{3}.
Arc length and sector area are proportional to the ratio of the central angle to 360360^\circ.
2
Calculate the arc length of minor arc PQPQ.
\text{Arc length} = \frac{1}{3} \times 2\pi(6) = 4\pi \text{ units}.
Arc length equals the central angle fraction times the total circumference 2πr2\pi r.
3
Calculate the area of sector POQPOQ.
\text{Sector area} = \frac{1}{3} \times \pi(6^2) = 12\pi \text{ square units}.
Sector area equals the central angle fraction times the total circle area πr2\pi r^2.
4
Evaluate the given statements against the calculated values.
Statements asserting an arc length of 4π4\pi units and a sector area of 12π12\pi square units are true. Other statements miscalculate by omitting the fraction or adding incorrect boundary components.
Comparing calculated values confirms the valid choices.

Anahtar Kavram

Arc Length and Sector Area Formulas
Soru 102Soru

In the xyxy-plane, triangle PQRPQR has vertices at P(0,0)P(0, 0), Q(8,0)Q(8, 0), and R(2,6)R(2, 6). Point SS lies on segment PQPQ such that segment RSRS divides triangle PQRPQR into two regions of equal area. Point TT lies on segment QRQR such that segment STST is parallel to segment PRPR. What is the area of triangle QSTQST?

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Cevap: 6

Cevap

6
The area of triangle PQRPQR is calculated using base PQ=8PQ = 8 and height h=6h = 6, yielding 12×8×6=24\frac{1}{2} \times 8 \times 6 = 24. Since segment RSRS divides triangle PQRPQR into two regions of equal area that share the height from vertex RR, point SS must be the midpoint of PQPQ, making QS=4QS = 4. Because segment STST is parallel to segment PRPR, triangle QSTQST is similar to triangle QPRQPR with a side length ratio of QSQP=48=12\frac{QS}{QP} = \frac{4}{8} = \frac{1}{2}. The ratio of the areas of similar triangles is the square of the side ratio, (12)2=14\left(\frac{1}{2}\right)^2 = \frac{1}{4}. Multiplying the total area 2424 by 14\frac{1}{4} gives the area of triangle QSTQST as 66.

Adım Adım Çözüm

1
Calculate the area of the main triangle PQRPQR.
Area(PQR)=12×8×6=24\text{Area}(PQR) = \frac{1}{2} \times 8 \times 6 = 24.
The base PQPQ lies along the x-axis with length 80=88 - 0 = 8, and the perpendicular height from vertex R(2,6)R(2,6) to the base is 66.
2
Determine the length of segment QSQS.
QS=4QS = 4.
Line segment RSRS splits PQR\triangle PQR into two smaller triangles, PSR\triangle PSR and QSR\triangle QSR, which share the same altitude from vertex RR. For their areas to be equal, their base lengths PSPS and SQSQ must be equal. Therefore, SS is the midpoint of PQPQ, giving QS=82=4QS = \frac{8}{2} = 4.
3
Establish the similarity relationship and scale factor between QST\triangle QST and QPR\triangle QPR.
QSTQPR\triangle QST \sim \triangle QPR with scale factor k=12k = \frac{1}{2}.
Because segment STST is parallel to segment PRPR, corresponding angles are equal (QST=QPR\angle QST = \angle QPR and QTS=QRP\angle QTS = \angle QRP). Thus, QST\triangle QST is similar to QPR\triangle QPR. The ratio of corresponding side lengths is QSQP=48=12\frac{QS}{QP} = \frac{4}{8} = \frac{1}{2}.
4
Compute the area of triangle QSTQST.
Area(QST)=6\text{Area}(QST) = 6.
The ratio of the areas of similar triangles is equal to the square of their linear scale factor: Area(QST)=(12)2×Area(PQR)=14×24=6\text{Area}(QST) = \left(\frac{1}{2}\right)^2 \times \text{Area}(PQR) = \frac{1}{4} \times 24 = 6.

Anahtar Kavram

Area of triangles, midpoint area partitioning, and area ratio scaling in similar triangles
Tahmini Süre:2m 0s
Soru 103Soru

In ABC\triangle ABC, the measure of A\angle A is 4545^\circ, the measure of C\angle C is 3030^\circ, and the length of side ACAC is 6+236 + 2\sqrt{3}. What is the length of side ABAB?

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Cevap: 262\sqrt{6}

Cevap

The length of side ABAB is 262\sqrt{6}.
The correct answer is 262\sqrt{6}. By drawing altitude BDBD from vertex BB to side ACAC, ABC\triangle ABC is decomposed into right triangle BDABDA (a 45459045^\circ-45^\circ-90^\circ triangle) and right triangle BDCBDC (a 30609030^\circ-60^\circ-90^\circ triangle). Setting altitude BD=xBD = x gives AD=xAD = x and CD=x3CD = x\sqrt{3}. Combining these gives AC=x+x3=x(1+3)AC = x + x\sqrt{3} = x(1 + \sqrt{3}). Equating this to 6+23=23(1+3)6 + 2\sqrt{3} = 2\sqrt{3}(1 + \sqrt{3}) gives x=23x = 2\sqrt{3}. The hypotenuse ABAB of the 45459045^\circ-45^\circ-90^\circ triangle is x2=(23)2=26x\sqrt{2} = (2\sqrt{3})\sqrt{2} = 2\sqrt{6}.

Adım Adım Çözüm

1
Draw altitude BDBD perpendicular to side ACAC with point DD lying on segment ACAC.
ABC\triangle ABC is partitioned into two adjacent right triangles: BDA\triangle BDA and BDC\triangle BDC.
Constructing an interior altitude allows the application of special right triangle ratio rules.
2
Analyze BDC\triangle BDC (30609030^\circ-60^\circ-90^\circ right triangle).
If BD=xBD = x, then CD=x3CD = x\sqrt{3} and BC=2xBC = 2x.
In a 30609030^\circ-60^\circ-90^\circ triangle, sides opposite the angles are in the ratio 1:3:21 : \sqrt{3} : 2.
3
Analyze BDA\triangle BDA (45459045^\circ-45^\circ-90^\circ right triangle).
AD=BD=xAD = BD = x, and hypotenuse AB=x2AB = x\sqrt{2}.
In a 45459045^\circ-45^\circ-90^\circ isosceles right triangle, legs are equal and the hypotenuse is leg×2\text{leg} \times \sqrt{2}.
4
Set up an equation for total side length AC=AD+CDAC = AD + CD.
x+x3=6+23    x(1+3)=23(1+3)    x=23x + x\sqrt{3} = 6 + 2\sqrt{3} \implies x(1 + \sqrt{3}) = 2\sqrt{3}(1 + \sqrt{3}) \implies x = 2\sqrt{3}.
Segment addition postulate combines ADAD and CDCD to match given total length ACAC.
5
Calculate requested side length ABAB.
AB=x2=(23)(2)=26AB = x\sqrt{2} = (2\sqrt{3})(\sqrt{2}) = 2\sqrt{6}.
Substitute x=23x = 2\sqrt{3} into the expression for hypotenuse ABAB.

Anahtar Kavram

Partitioning non-right triangles into 30609030^\circ-60^\circ-90^\circ and 45459045^\circ-45^\circ-90^\circ special right triangles by constructing an altitude.
Soru 104Soru

In the xyxy-plane, line kk passes through the origin (0,0)(0,0) and the point (4,3)(4, 3). Line mm is perpendicular to line kk and intersects line kk at point (4,3)(4, 3). If line mm intersects the xx-axis at point QQ and the yy-axis at point RR, what is the distance between point QQ and point RR?

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Cevap: 12512\frac{125}{12}

Cevap

12512\frac{125}{12}
The correct answer is derived by finding the slope of line kk as 34\frac{3}{4}, taking its negative reciprocal 43-\frac{4}{3} as the slope of perpendicular line mm, using the point (4,3)(4,3) to form line mm's equation y=43x+253y = -\frac{4}{3}x + \frac{25}{3}, identifying intercepts Q(254,0)Q\left(\frac{25}{4}, 0\right) and R(0,253)R\left(0, \frac{25}{3}\right), and applying the distance formula to obtain (254)2+(253)2=12512\sqrt{\left(\frac{25}{4}\right)^2 + \left(\frac{25}{3}\right)^2} = \frac{125}{12}.

Adım Adım Çözüm

1
Determine the slope of line kk
The slope of line kk is mk=3040=34m_k = \frac{3 - 0}{4 - 0} = \frac{3}{4}.
The slope of a line passing through (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2) is given by y2y1x2x1\frac{y_2 - y_1}{x_2 - x_1}.
2
Find the equation of line mm
Line mm has slope mm=43m_m = -\frac{4}{3} and equation y3=43(x4)    y=43x+253y - 3 = -\frac{4}{3}(x - 4) \implies y = -\frac{4}{3}x + \frac{25}{3}.
Perpendicular lines have slopes that are negative reciprocals of each other (mm=1mkm_m = -\frac{1}{m_k}). Point-slope form is used with point (4,3)(4, 3).
3
Calculate the intercepts QQ and RR
xx-intercept Q=(254,0)Q = \left(\frac{25}{4}, 0\right) and yy-intercept R=(0,253)R = \left(0, \frac{25}{3}\right).
Setting y=0y = 0 in y=43x+253y = -\frac{4}{3}x + \frac{25}{3} gives x=254x = \frac{25}{4}. Setting x=0x = 0 gives y=253y = \frac{25}{3}.
4
Compute the distance between QQ and RR
Distance d=(254)2+(253)2=25116+19=2525144=25×512=12512d = \sqrt{\left(\frac{25}{4}\right)^2 + \left(\frac{25}{3}\right)^2} = 25 \sqrt{\frac{1}{16} + \frac{1}{9}} = 25 \sqrt{\frac{25}{144}} = 25 \times \frac{5}{12} = \frac{125}{12}.
Applying the distance formula d=(x2x1)2+(y2y1)2d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} for points QQ and RR.

Anahtar Kavram

Perpendicular slopes and distance formula in coordinate geometry
Tahmini Süre:2m 0s
Soru 105Soru

An altitude of an acute triangle divides its base into two adjacent segments of lengths 55 and 99. If the area of the triangle is 8484 square units, what is the perimeter of the triangle?

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Cevap: 4242

Cevap

The perimeter of the triangle is 4242.
The base of the triangle is the sum of the two adjacent segments, 5+9=145 + 9 = 14. Setting up the area formula gives 84=12×14×h84 = \frac{1}{2} \times 14 \times h, which yields an altitude height of h=12h = 12. The altitude creates two right triangles: one with legs 55 and 1212 (hypotenuse 52+122=13\sqrt{5^2 + 12^2} = 13) and another with legs 99 and 1212 (hypotenuse 92+122=15\sqrt{9^2 + 12^2} = 15). Adding all three side lengths (14+13+1514 + 13 + 15) yields 4242.

Adım Adım Çözüm

1
Find the total base length and calculate the height (altitude) of the triangle.
Base =5+9=14= 5 + 9 = 14. Height h=2×Areabase=2×8414=12h = \frac{2 \times \text{Area}}{\text{base}} = \frac{2 \times 84}{14} = 12.
The area of a triangle is given by A=12bhA = \frac{1}{2} b h.
2
Calculate the lengths of the two non-base sides using the Pythagorean theorem on the two right triangles formed by the altitude.
Left side =52+122=25+144=13= \sqrt{5^2 + 12^2} = \sqrt{25 + 144} = 13. Right side =92+122=81+144=15= \sqrt{9^2 + 12^2} = \sqrt{81 + 144} = 15.
An altitude drawn to the base creates two right triangles sharing the altitude as a common leg.
3
Sum all three boundary sides to find the perimeter.
Perimeter =14+13+15=42= 14 + 13 + 15 = 42.
Perimeter is the total length around the outside of the triangle.

Anahtar Kavram

Area and perimeter of triangles split by an altitude using the Pythagorean theorem.
Tahmini Süre:1m 30s
Soru 106Soru

Three adjacent faces of a right rectangular prism have surface areas of 2424, 3636, and 5454 square centimeters. What is the volume of the prism, in cubic centimeters?

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Cevap: 216

Cevap

The volume of the rectangular prism is 216216 cubic centimeters.
Let the edge lengths of the right rectangular prism be ll, ww, and hh. The areas of three adjacent faces meeting at a common vertex are given by lw=24lw = 24, wh=36wh = 36, and lh=54lh = 54. Multiplying these three equations together yields (lw)(wh)(lh)=(lwh)2=24×36×54=46,656(lw)(wh)(lh) = (lwh)^2 = 24 \times 36 \times 54 = 46,656. Since the volume VV of a right rectangular prism is equal to lwhlwh, taking the positive square root gives V=46,656=216V = \sqrt{46,656} = 216 cubic centimeters.

Adım Adım Çözüm

1
Define variables for the three dimensions of the rectangular prism.
Let ll, ww, and hh represent the length, width, and height of the prism.
The area of each rectangular face is the product of two adjacent dimensions.
2
Express the given face areas in terms of the dimensions.
lw=24lw = 24, wh=36wh = 36, and lh=54lh = 54.
Adjacent faces share pairwise dimensions.
3
Multiply all three face area equations together.
(lw)(wh)(lh)=l2w2h2=(lwh)2=24×36×54=46,656(lw)(wh)(lh) = l^2 w^2 h^2 = (lwh)^2 = 24 \times 36 \times 54 = 46,656.
Multiplying the three face areas yields the square of the prism's volume (V=lwhV = lwh).
4
Calculate the square root of the product to determine the volume.
V=lwh=46,656=216V = lwh = \sqrt{46,656} = 216.
Taking the square root gives the volume directly without needing to solve for individual edge lengths.

Anahtar Kavram

For a right rectangular prism with adjacent face areas A1A_1, A2A_2, and A3A_3, the volume is given by V=A1×A2×A3V = \sqrt{A_1 \times A_2 \times A_3}.
Tahmini Süre:1m 15s
Soru 107Soru

In right triangle ABCABC, the measure of angle CC is 9090^\circ. Point DD lies on segment ACAC such that AD=11AD = 11 and BD=13BD = 13. If DC=5DC = 5, what is the perimeter of triangle ABDABD?

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Cevap: 44

Cevap

The perimeter of triangle ABDABD is 4444.
To find the perimeter of triangle ABDABD, we need the lengths of its three sides: ADAD, BDBD, and ABAB. We are given AD=11AD = 11 and BD=13BD = 13. To find ABAB, we first analyze right triangle BCDBCD with right angle at CC, hypotenuse BD=13BD = 13, and leg DC=5DC = 5. Using the Pythagorean theorem, leg BC=13252=12BC = \sqrt{13^2 - 5^2} = 12. Next, the full leg AC=AD+DC=11+5=16AC = AD + DC = 11 + 5 = 16. In right triangle ABCABC, legs are AC=16AC = 16 and BC=12BC = 12, making hypotenuse AB=162+122=20AB = \sqrt{16^2 + 12^2} = 20. Finally, the perimeter of triangle ABDABD is 11+13+20=4411 + 13 + 20 = 44.

Adım Adım Çözüm

1
Find the length of side BCBC using right triangle BCDBCD
BC=12BC = 12
In right triangle BCDBCD, angle C=90C = 90^\circ, hypotenuse BD=13BD = 13, and leg DC=5DC = 5. By the Pythagorean theorem, BC=13252=144=12BC = \sqrt{13^2 - 5^2} = \sqrt{144} = 12.
2
Determine the total length of side ACAC
AC=16AC = 16
Since point DD lies on segment ACAC, AC=AD+DC=11+5=16AC = AD + DC = 11 + 5 = 16.
3
Calculate the hypotenuse ABAB of the main right triangle ABCABC
AB=20AB = 20
In right triangle ABCABC, legs are AC=16AC = 16 and BC=12BC = 12. By the Pythagorean theorem, AB=162+122=256+144=400=20AB = \sqrt{16^2 + 12^2} = \sqrt{256 + 144} = \sqrt{400} = 20.
4
Calculate the perimeter of triangle ABDABD
Perimeter =44= 44
The sides of triangle ABDABD are AD=11AD = 11, BD=13BD = 13, and AB=20AB = 20. Adding these gives 11+13+20=4411 + 13 + 20 = 44.

Anahtar Kavram

Pythagorean Theorem and Multi-Step Triangle Properties
Soru 108Soru

An isosceles triangle has two sides of length 1010 units each and a third side of integer length xx units. If the area of the triangle is strictly greater than 2424 square units and less than or equal to 4848 square units, which of the following could be the value of xx? Select all such values.

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Cevap: 6; 16

Cevap

The values 6 and 16 are the valid side lengths.
The values 6 and 16 produce valid areas of approximately 28.62 and exactly 48 square units respectively, both of which satisfy the given condition that the area must be strictly greater than 24 and less than or equal to 48.

Adım Adım Çözüm

1
Express the height and area of the isosceles triangle in terms of xx.
Height h=102(x/2)2=100x24h = \sqrt{10^2 - (x/2)^2} = \sqrt{100 - \frac{x^2}{4}}, so Area A=12x100x24=14x400x2A = \frac{1}{2} x \sqrt{100 - \frac{x^2}{4}} = \frac{1}{4} x \sqrt{400 - x^2}.
The altitude to the base of an isosceles triangle bisects the base into two equal segments of length x2\frac{x}{2}.
2
Set up the inequality for the area constraints 24<A4824 < A \le 48.
24<14x400x248    96<x400x219224 < \frac{1}{4} x \sqrt{400 - x^2} \le 48 \implies 96 < x \sqrt{400 - x^2} \le 192.
Multiplying all parts by 44 isolates the radical expression.
3
Square all terms to analyze the function f(x2)=x2(400x2)f(x^2) = x^2(400 - x^2).
9216<x2(400x2)368649216 < x^2(400 - x^2) \le 36864.
Squaring positive quantities preserves the inequality direction.
4
Evaluate the area function for each given option choice.
For x=4x=4: A19.6A \approx 19.6 (too small). For x=6x=6: A28.6A \approx 28.6 (valid). For x=14x=14: A50.0A \approx 50.0 (too large). For x=16x=16: A=48A = 48 (valid). For x=20x=20: degenerate triangle with A=0A = 0 (invalid).
Direct evaluation identifies which integer choices satisfy 24<A4824 < A \le 48.

Anahtar Kavram

Properties of isosceles triangles, Pythagorean theorem for altitude, area bounds, and triangle inequality.
Soru 109Soru

In the right rectangular solid ABCDEFGHABCDEFGH, the base ABCDABCD is a rectangle with edge lengths AB=6AB = 6 and BC=63BC = 6\sqrt{3}. The vertical edge CG=12CG = 12. Point MM is the midpoint of edge CGCG. What is the perimeter of triangle BDMBDM?

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Cevap: 24+6224 + 6\sqrt{2}

Cevap

The perimeter of triangle BDMBDM is 24+6224 + 6\sqrt{2}.
The correct answer is obtained by recognizing three right triangles within the 3D figure: BCD\triangle BCD has legs 66 and 636\sqrt{3} giving BD=12BD = 12; BCM\triangle BCM has legs 636\sqrt{3} and 66 giving BM=12BM = 12; and DCM\triangle DCM has legs 66 and 66 giving DM=62DM = 6\sqrt{2}. Summing the three sides yields a perimeter of 24+6224 + 6\sqrt{2}.

Adım Adım Çözüm

1
Calculate the length of base diagonal BDBD using the right triangle BCD\triangle BCD.
BD=12BD = 12
In right triangle BCD\triangle BCD, legs are CD=AB=6CD = AB = 6 and BC=63BC = 6\sqrt{3}. Using the 30609030^\circ\text{--}60^\circ\text{--}90^\circ ratio (1:3:2)(1 : \sqrt{3} : 2), hypotenuse BD=2×6=12BD = 2 \times 6 = 12 (or via Pythagorean theorem: BD=62+(63)2=36+108=144=12BD = \sqrt{6^2 + (6\sqrt{3})^2} = \sqrt{36 + 108} = \sqrt{144} = 12).
2
Calculate the length of segment BMBM using the right triangle BCM\triangle BCM.
BM=12BM = 12
Since MM is the midpoint of vertical edge CG=12CG = 12, CM=6CM = 6. Vertical edge CGCG is perpendicular to base ABCDABCD, so BCM\triangle BCM is a right triangle at CC. The legs are CM=6CM = 6 and BC=63BC = 6\sqrt{3}. Applying the 30609030^\circ\text{--}60^\circ\text{--}90^\circ ratio (1:3:2)(1 : \sqrt{3} : 2), hypotenuse BM=2×6=12BM = 2 \times 6 = 12.
3
Calculate the length of segment DMDM using the right triangle DCM\triangle DCM.
DM=62DM = 6\sqrt{2}
In right triangle DCM\triangle DCM, legs are CD=6CD = 6 and CM=6CM = 6. Since the legs are equal, DCM\triangle DCM is a 45459045^\circ\text{--}45^\circ\text{--}90^\circ isosceles right triangle with side ratio 1:1:21 : 1 : \sqrt{2}. Thus, hypotenuse DM=62DM = 6\sqrt{2}.
4
Sum the three side lengths to find the perimeter of BDM\triangle BDM.
Perimeter = 12+12+62=24+6212 + 12 + 6\sqrt{2} = 24 + 6\sqrt{2}
The perimeter of BDM\triangle BDM is BD+BM+DMBD + BM + DM.

Anahtar Kavram

Applying special right triangle ratios (30609030^\circ\text{--}60^\circ\text{--}90^\circ and 45459045^\circ\text{--}45^\circ\text{--}90^\circ) to 3D rectangular solids.
Soru 110Soru

A solid cube has a total surface area of SS and a volume of VV. A solid right circular cylinder has a height equal to its base diameter. If the total surface area of the cylinder is also equal to SS, what is the volume of the cylinder in terms of VV?

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Cevap: 2πV\frac{2}{\sqrt{\pi}} V

Cevap

2πV\frac{2}{\sqrt{\pi}} V
The total surface area of a cube with edge aa is 6a26a^2 and its volume is V=a3V = a^3. For a cylinder with base radius rr and height h=2rh = 2r, the total surface area is 2πr2+2πr(2r)=6πr22\pi r^2 + 2\pi r(2r) = 6\pi r^2. Setting 6πr2=6a26\pi r^2 = 6a^2 yields r=aπr = \frac{a}{\sqrt{\pi}} and h=2aπh = \frac{2a}{\sqrt{\pi}}. Substituting these into the volume formula Vcyl=πr2hV_{\text{cyl}} = \pi r^2 h produces π(a2π)(2aπ)=2a3π=2πV\pi \left(\frac{a^2}{\pi}\right) \left(\frac{2a}{\sqrt{\pi}}\right) = \frac{2a^3}{\sqrt{\pi}} = \frac{2}{\sqrt{\pi}} V.

Adım Adım Çözüm

1
Express the surface area and volume of the cube in terms of its side length aa.
Surface area S=6a2S = 6a^2 and volume V=a3V = a^3.
A cube with edge length aa has 66 identical square faces of area a2a^2 and volume a3a^3.
2
Set up the total surface area formula for the cylinder with radius rr and height h=2rh = 2r, and equate it to SS.
Total surface area Scyl=2πr2+2πrh=2πr2+2πr(2r)=6πr2=6a2S_{\text{cyl}} = 2\pi r^2 + 2\pi r h = 2\pi r^2 + 2\pi r (2r) = 6\pi r^2 = 6a^2.
The cylinder's height is equal to its base diameter (2r2r). Equating surface areas gives 6πr2=6a26\pi r^2 = 6a^2.
3
Solve for radius rr in terms of edge length aa.
r2=a2π    r=aπr^2 = \frac{a^2}{\pi} \implies r = \frac{a}{\sqrt{\pi}}.
Dividing both sides by 6π6\pi and taking the square root isolates rr.
4
Calculate the volume of the cylinder in terms of VV.
Vcyl=πr2h=π(a2π)(2aπ)=2a3π=2πVV_{\text{cyl}} = \pi r^2 h = \pi \left(\frac{a^2}{\pi}\right) \left(\frac{2a}{\sqrt{\pi}}\right) = \frac{2a^3}{\sqrt{\pi}} = \frac{2}{\sqrt{\pi}} V.
Substituting r2=a2πr^2 = \frac{a^2}{\pi} and h=2aπh = \frac{2a}{\sqrt{\pi}} into the cylinder volume formula πr2h\pi r^2 h yields the answer in terms of V=a3V = a^3.

Anahtar Kavram

Volume and surface area relationship between geometric solids
Tahmini Süre:2m 0s
Soru 111Soru

In triangle ABCABC, the length of side ABAB is 1616 units and the length of side ACAC is 1313 units. If the area of triangle ABCABC is 9696 square units and the altitude from vertex CC to side ABAB intersects the line segment ABAB at point DD, what is the length of segment ADAD?

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Cevap: 55

Cevap

The length of segment ADAD is 55 units.
The correct answer is 55. First, find altitude CDCD using the triangle area equation: Area=12×base×height    96=12×16×CD    CD=12\text{Area} = \frac{1}{2} \times \text{base} \times \text{height} \implies 96 = \frac{1}{2} \times 16 \times CD \implies CD = 12. Next, because CDABCD \perp AB, triangle ADCADC is a right triangle with hypotenuse AC=13AC = 13 and leg CD=12CD = 12. Applying the Pythagorean theorem yields AD=132122=25=5AD = \sqrt{13^2 - 12^2} = \sqrt{25} = 5.

Adım Adım Çözüm

1
Calculate the length of altitude CDCD using the triangle area formula.
CD=12CD = 12 units.
The area of triangle ABCABC is given by Area=12×AB×CD\text{Area} = \frac{1}{2} \times AB \times CD. Substituting the given values: 96=12×16×CD    96=8×CD    CD=1296 = \frac{1}{2} \times 16 \times CD \implies 96 = 8 \times CD \implies CD = 12.
2
Apply the Pythagorean theorem in right triangle ADCADC to find ADAD.
AD=5AD = 5 units.
Altitude CDCD is perpendicular to ABAB, forming right triangle ADCADC with hypotenuse AC=13AC = 13 and leg CD=12CD = 12. By the Pythagorean theorem, AD2+CD2=AC2    AD2+122=132    AD2+144=169    AD2=25    AD=5AD^2 + CD^2 = AC^2 \implies AD^2 + 12^2 = 13^2 \implies AD^2 + 144 = 169 \implies AD^2 = 25 \implies AD = 5.

Anahtar Kavram

Triangles: Properties, Perimeter, and Area
Tahmini Süre:1m 30s
Soru 112Soru

The sum of the measures of all interior angles of a convex polygon, excluding one interior angle θ\theta, is equal to 21902190^\circ. If the degree measure of θ\theta is an integer, what is the perimeter of a regular polygon with nn sides, where nn is the number of sides of the original polygon and each side length is θ10\frac{\theta}{10} units?

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Cevap: 225

Cevap

The perimeter of the regular polygon is 225.
The sum of the interior angles of a convex polygon with nn sides is (n2)×180(n-2) \times 180^\circ. Adding the excluded interior angle θ\theta to 21902190^\circ yields the total sum SS. Because 0<θ<1800^\circ < \theta < 180^\circ, SS must fall strictly between 21902190^\circ and 23702370^\circ. The only multiple of 180180^\circ in this interval is 23402340^\circ. Setting (n2)×180=2340(n-2)\times 180^\circ = 2340^\circ yields n=15n = 15. Solving for θ\theta gives θ=23402190=150\theta = 2340^\circ - 2190^\circ = 150^\circ. The side length is 15010=15\frac{150}{10} = 15, making the perimeter 15×15=22515 \times 15 = 225.

Adım Adım Çözüm

1
Set up the inequality for the sum of interior angles of a convex polygon.
The total sum of interior angles for a convex nn-gon is S=(n2)×180S = (n-2) \times 180^\circ. Given Sθ=2190S - \theta = 2190^\circ, we have S=2190+θS = 2190^\circ + \theta.
The sum of interior angles of any convex polygon with nn sides is (n2)×180(n-2) \times 180^\circ.
2
Determine the value of SS using the bounds for an interior angle of a convex polygon.
Since 0<θ<1800^\circ < \theta < 180^\circ, it follows that 2190<S<2190+180=23702190^\circ < S < 2190^\circ + 180^\circ = 2370^\circ. The only multiple of 180180^\circ in this range is 23402340^\circ.
SS must be an integer multiple of 180180^\circ and θ\theta must be strictly between 00^\circ and 180180^\circ.
3
Calculate the number of sides nn and the missing angle θ\theta.
(n2)×180=2340    n2=13    n=15(n-2) \times 180^\circ = 2340^\circ \implies n - 2 = 13 \implies n = 15. Then θ=23402190=150\theta = 2340^\circ - 2190^\circ = 150^\circ.
Solving the linear equations gives exact values for the number of sides and the excluded angle.
4
Compute the perimeter of the regular regular nn-gon.
Side length =θ10=15010=15= \frac{\theta}{10} = \frac{150}{10} = 15. Perimeter =n×side length=15×15=225= n \times \text{side length} = 15 \times 15 = 225.
The perimeter of a regular polygon is the product of its number of sides and its individual side length.

Anahtar Kavram

Sum of Interior Angles of Convex Polygons
Tahmini Süre:2m 0s
Soru 113Soru

A triangle has side lengths of xx, x+4x + 4, and 1414 units, where xx is an integer. Which of the following could be the perimeter of the triangle? Select all that apply.

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Cevap: 3030; 3434; 4040

Cevap

The possible perimeters of the triangle are 30, 34, and 40.
The Triangle Inequality Theorem dictates that the sum of the lengths of any two sides of a triangle must be strictly greater than the length of the remaining side. For side lengths xx, x+4x + 4, and 1414, setting x+(x+4)>14x + (x + 4) > 14 yields 2x>102x > 10, so x>5x > 5. Since xx is specified as an integer, xx can be any integer greater than or equal to 6. Substituting valid values of xx into the perimeter formula P=2x+18P = 2x + 18 gives possible perimeters of 30 (when x=6x = 6), 34 (when x=8x = 8), and 40 (when x=11x = 11). Thus, the values 30, 34, and 40 are all valid perimeters.

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1
Apply the Triangle Inequality Theorem
x>5x > 5
According to the Triangle Inequality Theorem, the sum of any two side lengths must be strictly greater than the third side length. Therefore, x+(x+4)>14x + (x + 4) > 14, which simplifies to 2x+4>14    2x>10    x>52x + 4 > 14 \implies 2x > 10 \implies x > 5. The other two inequality conditions ((x+4)+14>x(x + 4) + 14 > x and x+14>x+4x + 14 > x + 4) are satisfied for all positive values of xx.
2
Express the perimeter in terms of xx
P=2x+18P = 2x + 18
The perimeter PP is the sum of the three side lengths: P=x+(x+4)+14=2x+18P = x + (x + 4) + 14 = 2x + 18.
3
Evaluate the given choices against the valid bounds of xx
Valid integer values of x6x \ge 6 correspond to perimeters P30P \ge 30 that are even numbers.
Since xx is an integer and x>5x > 5, the minimum integer value for xx is 6, which yields a minimum perimeter of P=2(6)+18=30P = 2(6) + 18 = 30. Testing each option:
- For 26: 2x+18=26    x=42x + 18 = 26 \implies x = 4 (Invalid, x5x \le 5)
- For 28: 2x+18=28    x=52x + 18 = 28 \implies x = 5 (Invalid, x5x \le 5)
- For 30: 2x+18=30    x=62x + 18 = 30 \implies x = 6 (Valid)
- For 34: 2x+18=34    x=82x + 18 = 34 \implies x = 8 (Valid)
- For 40: 2x+18=40    x=112x + 18 = 40 \implies x = 11 (Valid)

Anahtar Kavram

Triangle Inequality Theorem and Perimeter Calculation
Soru 114Soru

In the xyxy-plane, line L1L_1 is defined by the equation 2x3y=62x - 3y = 6. Line L2L_2 is perpendicular to line L1L_1 and passes through the point P(4,1)P(4, -1). Point Q(a,b)Q(a, b) lies on line L2L_2 such that the distance between point PP and point QQ is 13\sqrt{13}. Which of the following statements regarding point QQ or line L2L_2 could be true? Select all such statements.

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Cevap: Point QQ lies in Quadrant I.; The sum of the coordinates of point QQ, a+ba + b, is equal to 44.; The distance from point QQ to the origin is 2132\sqrt{13}.

Cevap

The correct statements are that point Q can lie in Quadrant I, the sum of the coordinates of point Q can equal 4, and the distance from point Q to the origin can be 2√13.
Solving the system formed by line L2L_2 (3x+2y=103x + 2y = 10) and the distance constraint (a4)2+(b+1)2=13(a-4)^2 + (b+1)^2 = 13 yields two possible points: (2,2)(2, 2) and (6,4)(6, -4). The point (2,2)(2, 2) lies in Quadrant I and has a coordinate sum of 2+2=42 + 2 = 4. The point (6,4)(6, -4) has a distance to the origin of 62+(4)2=52=213\sqrt{6^2 + (-4)^2} = \sqrt{52} = 2\sqrt{13}.

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1
Determine the slope and equation of line L2L_2.
Line L1L_1 has slope m1=23m_1 = \frac{2}{3}. Therefore, perpendicular line L2L_2 has slope m2=32m_2 = -\frac{3}{2}. Using point P(4,1)P(4, -1), the equation of L2L_2 is y(1)=32(x4)y - (-1) = -\frac{3}{2}(x - 4), which simplifies to y=32x+5y = -\frac{3}{2}x + 5 or 3x+2y=103x + 2y = 10.
Perpendicular lines in the coordinate plane have negative reciprocal slopes.
2
Express the distance constraint between P(4,1)P(4, -1) and Q(a,b)Q(a, b) algebraically.
Since Q(a,b)Q(a, b) lies on L2L_2, b=32a+5b = -\frac{3}{2}a + 5. The distance squared is (a4)2+(b+1)2=13(a - 4)^2 + (b + 1)^2 = 13. Substituting b+1=32(a4)b + 1 = -\frac{3}{2}(a - 4) yields (a4)2+(32(a4))2=13(a - 4)^2 + \left(-\frac{3}{2}(a - 4)\right)^2 = 13, which simplifies to 134(a4)2=13\frac{13}{4}(a - 4)^2 = 13, so (a4)2=4(a - 4)^2 = 4.
Applying the distance formula and substituting the line equation reduces the problem to a quadratic equation in one variable.
3
Solve for the possible coordinates of point QQ.
Taking square roots gives a4=2a - 4 = 2 or a4=2a - 4 = -2, resulting in a=6a = 6 or a=2a = 2. Correspondingly, b=4b = -4 or b=2b = 2. Thus, QQ can be (6,4)(6, -4) or (2,2)(2, 2).
Quadratic equations of the form (xh)2=k(x-h)^2 = k have two real solutions.
4
Evaluate each statement against the possible coordinates Q(6,4)Q(6, -4) and Q(2,2)Q(2, 2).
For Q(2,2)Q(2, 2): it lies in Quadrant I (valid), its coordinate sum is 2+2=42 + 2 = 4 (valid). For Q(6,4)Q(6, -4): its distance to the origin is 62+(4)2=52=213\sqrt{6^2 + (-4)^2} = \sqrt{52} = 2\sqrt{13} (valid). The yy-intercept of L2L_2 is (0,5)(0, 5), and (4,2)(4, 2) is not on L2L_2.
Direct verification confirms which properties hold for the two solved points.

Anahtar Kavram

Perpendicular Slopes and Distance Formula in Coordinate Geometry
Soru 115Soru

A right circular cylinder has a base radius of rr and a height of hh. If the base radius is doubled and the height is halved to create a new right circular cylinder, which of the following statements must be true? Select all that apply.

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Cevap: The volume of the new cylinder is twice the volume of the original cylinder.; The lateral surface area of the new cylinder is equal to the lateral surface area of the original cylinder.; The area of the circular base of the new cylinder is four times the area of the circular base of the original cylinder.

Cevap

The correct statements are: the volume of the new cylinder is twice the volume of the original cylinder, the lateral surface area of the new cylinder is equal to the lateral surface area of the original cylinder, and the area of the circular base of the new cylinder is four times the area of the circular base of the original cylinder.
The volume formula V=πr2hV = \pi r^2 h scales by 22×12=22^2 \times \frac{1}{2} = 2, so volume doubles. The lateral surface area formula L=2πrhL = 2\pi r h scales by 2×12=12 \times \frac{1}{2} = 1, remaining unchanged. The base area formula A=πr2A = \pi r^2 scales by 22=42^2 = 4, quadrupling the area.

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1
Write down the original formulas for a cylinder with radius rr and height hh.
Base Area A1=πr2A_1 = \pi r^2, Lateral Surface Area L1=2πrhL_1 = 2\pi r h, Total Surface Area T1=2πrh+2πr2T_1 = 2\pi r h + 2\pi r^2, Volume V1=πr2hV_1 = \pi r^2 h.
Establish baseline geometric properties.
2
Substitute the new dimensions r=2rr' = 2r and h=h2h' = \frac{h}{2} into each formula.
New Base Area A2=π(2r)2=4πr2=4A1A_2 = \pi (2r)^2 = 4\pi r^2 = 4A_1.
New Lateral Surface Area L2=2π(2r)(h2)=2πrh=L1L_2 = 2\pi (2r) \left(\frac{h}{2}\right) = 2\pi r h = L_1.
New Volume V2=π(2r)2(h2)=π(4r2)(h2)=2πr2h=2V1V_2 = \pi (2r)^2 \left(\frac{h}{2}\right) = \pi (4r^2) \left(\frac{h}{2}\right) = 2\pi r^2 h = 2V_1.
Calculate the updated values for each geometric property.
3
Evaluate each statement against the calculated values.
Volume doubles (V2=2V1V_2 = 2V_1), lateral surface area remains equal (L2=L1L_2 = L_1), and base area quadruples (A2=4A1A_2 = 4A_1).
Determine which options state correct mathematical relationships.

Anahtar Kavram

Scaling effects on 3D geometry formulas for right circular cylinders
Soru 116Soru

In the xyxy-plane, line L1L_1 has a positive slope mm and a yy-intercept of (0,4)(0, 4). The perpendicular distance from the origin (0,0)(0, 0) to line L1L_1 is 222\sqrt{2}. Line L2L_2 is perpendicular to line L1L_1 and passes through the points (2,1)(2, 1) and (6,k)(6, k). What is the value of kk?

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Cevap: 3-3

Cevap

3-3
The equation of line L1L_1 is mxy+4=0mx - y + 4 = 0. Using the distance formula from the origin to a line, 4m2+1=22\frac{4}{\sqrt{m^2 + 1}} = 2\sqrt{2}, which simplifies to m2+1=2m^2 + 1 = 2, yielding m=1m = 1. The slope of line L2L_2 is the negative reciprocal of 11, which is 1-1. Using the slope equation k162=1\frac{k - 1}{6 - 2} = -1, we find k1=4k - 1 = -4, giving k=3k = -3.

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1
Express line L1L_1 in standard form and set up the distance formula from the origin.
Line L1L_1 has slope mm and yy-intercept (0,4)(0,4), so its equation is y=mx+4y = mx + 4, or mxy+4=0mx - y + 4 = 0. The perpendicular distance dd from (0,0)(0,0) to Ax+By+C=0Ax + By + C = 0 is d=CA2+B2=4m2+1d = \frac{|C|}{\sqrt{A^2 + B^2}} = \frac{4}{\sqrt{m^2 + 1}}.
The shortest distance from a point to a line is given by the perpendicular distance formula.
2
Solve for the positive slope mm of line L1L_1.
Setting 4m2+1=22\frac{4}{\sqrt{m^2 + 1}} = 2\sqrt{2} yields m2+1=2\sqrt{m^2 + 1} = \sqrt{2}. Squaring both sides gives m2+1=2m^2 + 1 = 2, so m2=1m^2 = 1. Since m>0m > 0, m=1m = 1.
The problem specifies that line L1L_1 has a positive slope.
3
Determine the slope of line L2L_2.
Since line L2L_2 is perpendicular to line L1L_1, its slope m2m_2 is the negative reciprocal of mm: m2=11=1m_2 = -\frac{1}{1} = -1.
Perpendicular lines in the coordinate plane have slopes that are negative reciprocals of each other.
4
Use the slope formula with points (2,1)(2, 1) and (6,k)(6, k) to solve for kk.
m2=k162=k14=1    k1=4    k=3m_2 = \frac{k - 1}{6 - 2} = \frac{k - 1}{4} = -1 \implies k - 1 = -4 \implies k = -3.
Equating the slope calculated from two points to the known perpendicular slope solves for the missing coordinate.

Anahtar Kavram

Perpendicular Distance and Perpendicular Lines in Coordinate Geometry
Soru 117Soru

In the xyxy-plane, the parabola defined by y=2x28x+5y = 2x^2 - 8x + 5 is reflected across the line y=xy = x. The resulting curve is then translated 33 units to the right and 44 units downward to produce curve CC. If the point (a,1)(a, -1) lies on curve CC, what is the value of aa?

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Cevap: 2

Cevap

The value of aa is 22.
Completing the square yields y=2(x2)23y = 2(x - 2)^2 - 3. Reflecting across y=xy = x interchanges xx and yy, producing x=2(y2)23x = 2(y - 2)^2 - 3. Shifting this curve 33 units to the right replaces xx with x3x - 3, and shifting 44 units down replaces yy with y+4y + 4. The equation simplifies to x=2(y+2)2x = 2(y + 2)^2. Setting y=1y = -1 gives a=2(1+2)2=2a = 2(-1 + 2)^2 = 2.

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1
Rewrite the original parabola equation in vertex form.
y=2(x2)23y = 2(x - 2)^2 - 3
Expressing the parabola in vertex form makes tracking coordinate transformations straightforward.
2
Apply the reflection across the line y=xy = x.
x=2(y2)23x = 2(y - 2)^2 - 3
Reflecting across y=xy = x interchanges the xx and yy coordinates of every point on the graph.
3
Apply the translations to find the equation of curve CC.
x=2(y+2)2x = 2(y + 2)^2
Translating right by 33 replaces xx with x3x - 3, and translating down by 44 replaces yy with y+4y + 4.
4
Substitute y=1y = -1 into the equation for curve CC to calculate aa.
a=2a = 2
Since the point (a,1)(a, -1) lies on curve CC, substituting x=ax = a and y=1y = -1 yields a=2(1)2=2a = 2(1)^2 = 2.

Anahtar Kavram

Reflection across y=xy = x and rigid horizontal/vertical translations of conic sections
Soru 118Soru

In the xyxy-plane, point M(3,3)M(3, 3) is the midpoint of line segment ABAB, where point AA has coordinates (1,2)(1, 2). Line LL is perpendicular to line segment ABAB and passes through point BB. What is the xx-intercept of line LL?

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Cevap: 7

Cevap

7
Using the midpoint formula with A(1,2)A(1, 2) and M(3,3)M(3, 3) gives endpoint B(5,4)B(5, 4). The slope of segment ABAB is 4251=12\frac{4-2}{5-1} = \frac{1}{2}, so line LL, being perpendicular to ABAB, has slope 2-2. The equation of line LL passing through (5,4)(5, 4) is y4=2(x5)y - 4 = -2(x - 5), which simplifies to y=2x+14y = -2x + 14. Setting y=0y = 0 gives 0=2x+140 = -2x + 14, so the xx-intercept is 77.

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1
Calculate the coordinates of endpoint B using the midpoint formula.
Point B has coordinates (5,4)(5, 4).
Midpoint M(xm,ym)=(xA+xB2,yA+yB2)M(x_m, y_m) = \left(\frac{x_A + x_B}{2}, \frac{y_A + y_B}{2}\right). Solving 1+xB2=3\frac{1 + x_B}{2} = 3 yields xB=5x_B = 5, and solving 2+yB2=3\frac{2 + y_B}{2} = 3 yields yB=4y_B = 4.
2
Determine the slope of segment AB.
The slope mAB=12m_{AB} = \frac{1}{2}.
Using the slope formula m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1} between (1,2)(1, 2) and (5,4)(5, 4) gives 4251=24=12\frac{4 - 2}{5 - 1} = \frac{2}{4} = \frac{1}{2}.
3
Determine the slope of line L.
The slope of line L is 2-2.
Perpendicular lines have negative reciprocal slopes. The negative reciprocal of 12\frac{1}{2} is 2-2.
4
Find the equation of line L and solve for its x-intercept.
The x-intercept is 7.
Using point-slope form with B(5,4)B(5, 4) and m=2m = -2: y4=2(x5)    y=2x+14y - 4 = -2(x - 5) \implies y = -2x + 14. Setting y=0y = 0 gives 0=2x+14    x=70 = -2x + 14 \implies x = 7.

Anahtar Kavram

Midpoint Formula, Perpendicular Slopes, and Line Intercepts
Soru 119Soru

A line with a slope of 2-2 passes through the point (1,7)(1, 7) and contains the point P(a,3)P(a, 3). What is the distance between point PP and the point Q(11,3)Q(11, -3)?

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Cevap: 1010

Cevap

The distance between point PP and point QQ is 1010.
Using the slope definition m=ΔyΔxm = \frac{\Delta y}{\Delta x}, we set up 37a1=2\frac{3 - 7}{a - 1} = -2, which solves to a=3a = 3, giving point P(3,3)P(3, 3). Applying the distance formula d=(x2x1)2+(y2y1)2d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} between P(3,3)P(3, 3) and Q(11,3)Q(11, -3) yields (113)2+(33)2=64+36=10\sqrt{(11 - 3)^2 + (-3 - 3)^2} = \sqrt{64 + 36} = 10.

Adım Adım Çözüm

1
Use the slope formula to find the missing coordinate aa of point P(a,3)P(a, 3).
The slope m=y2y1x2x1=37a1=2m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{3 - 7}{a - 1} = -2, which simplifies to 4a1=2\frac{-4}{a - 1} = -2, yielding a1=2a - 1 = 2, so a=3a = 3.
The slope between any two points on a straight line must equal the given slope of 2-2.
2
Identify the coordinates of point PP.
Point PP has coordinates (3,3)(3, 3).
Substituting a=3a = 3 into P(a,3)P(a, 3) gives the exact position of PP.
3
Apply the distance formula between P(3,3)P(3, 3) and Q(11,3)Q(11, -3).
d=(113)2+(33)2=82+(6)2=64+36=100=10d = \sqrt{(11 - 3)^2 + (-3 - 3)^2} = \sqrt{8^2 + (-6)^2} = \sqrt{64 + 36} = \sqrt{100} = 10.
The distance formula calculates the Euclidean distance between two points in the coordinate plane.

Anahtar Kavram

Line slope equation and coordinate distance formula

Alternatif Yöntem

Find the line equation directly in slope-intercept form: y7=2(x1)    y=2x+9y - 7 = -2(x - 1) \implies y = -2x + 9. Substitute y=3y = 3 to get 3=2a+9    a=33 = -2a + 9 \implies a = 3. Then compute the distance between (3,3)(3, 3) and (11,3)(11, -3) using the standard distance formula.
Tahmini Süre:1m 30s
Soru 120Soru

In triangle PQRPQR, point SS lies on segment QRQR such that segment PSPS is perpendicular to QRQR. The length of altitude PSPS is 88 units. If the area of triangle PQRPQR is 5656 square units and the ratio of the area of triangle PQSPQS to the area of triangle PSRPSR is 3:43 : 4, what is the length of side PQPQ?

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Cevap: 1010

Cevap

10
The area of triangle PQRPQR is given as 56 square units and altitude PS=8PS = 8. Using Area=12×QR×8\text{Area} = \frac{1}{2} \times QR \times 8, we find QR=14QR = 14. Because triangles PQSPQS and PSRPSR share altitude PSPS, the ratio of their areas equals the ratio of their bases QS:SR=3:4QS : SR = 3 : 4. Dividing QR=14QR = 14 into 7 equal parts yields QS=6QS = 6. In right-angled triangle PQSPQS, legs are PS=8PS = 8 and QS=6QS = 6, giving hypotenuse PQ=82+62=10PQ = \sqrt{8^2 + 6^2} = 10.

Adım Adım Çözüm

1
Calculate the total length of base QRQR using the area of triangle PQRPQR.
Area=12×base×height    56=12×QR×8    56=4×QR    QR=14\text{Area} = \frac{1}{2} \times \text{base} \times \text{height} \implies 56 = \frac{1}{2} \times QR \times 8 \implies 56 = 4 \times QR \implies QR = 14.
The area formula for any triangle relates base, height, and total area.
2
Determine the length of segment QSQS using the given area ratio.
Since triangles PQSPQS and PSRPSR share the same altitude PSPS, their areas are proportional to their base lengths QSQS and SRSR. Therefore, QS:SR=3:4QS : SR = 3 : 4. The total parts are 3+4=73 + 4 = 7. Thus, QS=14×37=6QS = 14 \times \frac{3}{7} = 6.
Triangles sharing a common altitude have areas proportional to their respective bases.
3
Apply the Pythagorean theorem in right triangle PQSPQS to find hypotenuse PQPQ.
PQ2=PS2+QS2=82+62=64+36=100    PQ=10PQ^2 = PS^2 + QS^2 = 8^2 + 6^2 = 64 + 36 = 100 \implies PQ = 10.
Segment PSPS is perpendicular to QRQR, forming right-angled triangle PQSPQS with legs of length 8 and 6.

Anahtar Kavram

Area of triangles, common altitude area ratio, and the Pythagorean theorem.
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