Geometry

157 soru

Soru 1Soru →

A circular swimming pool has a circumference of 20π20\pi feet. What is the diameter of the pool in feet?

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Cevap: 20

Cevap

20
The formula for the circumference of a circle is C=πdC = \pi d. By substituting the given circumference of 20π20\pi into the formula, we get 20π=πd20\pi = \pi d. Dividing both sides by π\pi yields a diameter of 2020 feet.

Adım Adım Çözüm

1
Identify the formula for the circumference of a circle.
C=πdC = \pi d, where CC is circumference and dd is diameter.
This formula directly relates the given circumference to the unknown diameter.
2
Substitute the given value into the formula.
20π=πd20\pi = \pi d
The problem states the circumference is 20π20\pi feet.
3
Solve for the diameter (dd).
d=20d = 20
Dividing both sides of the equation by π\pi isolates the value of dd.

Anahtar Kavram

Circumference of a circle
Tahmini Süre:45s
Soru 2Soru →

Determine the missing side length based on the geometric properties of a right triangle.

Aşağıdaki boşlukları doldurun

In a right triangle, the two shorter sides (legs) measure 99 cm and 1212 cm. According to the Pythagorean theorem, the length of the hypotenuse is cm.
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Cevap

15
By applying the Pythagorean theorem (a2+b2=c2a^2 + b^2 = c^2) to a right triangle with legs of 99 and 1212, we square both numbers to get 8181 and 144144. Their sum is 225225. The hypotenuse is the square root of 225225, which is 1515.

Adım Adım Çözüm

1
Identify the known sides of the right triangle.
The legs (let's call them aa and bb) measure 99 cm and 1212 cm.
The Pythagorean theorem requires knowing the lengths of two sides to find the third.
2
Set up the Pythagorean theorem equation.
a2+b2=c2a^2 + b^2 = c^2, which becomes 92+122=c29^2 + 12^2 = c^2.
This formula relates the squares of the legs to the square of the hypotenuse (cc).
3
Square the lengths of the two legs and add them together.
81+144=22581 + 144 = 225
This calculation determines the value of c2c^2.
4
Take the square root of the sum to find the hypotenuse.
225=15\sqrt{225} = 15
Since c2=225c^2 = 225, taking the square root gives the actual length of the hypotenuse (cc).

Anahtar Kavram

Pythagorean Theorem
Soru 3Soru →

A rectangular swimming pool measures 4040 feet in length and 3030 feet in width. A concrete deck of uniform width is built around the entire outer edge of the pool. If the area of the concrete deck alone is 296296 square feet, what is the width of the deck, in feet?

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Cevap: 2

Cevap

2
The correct width is found by setting up an equation for the total area. The deck adds its width to both sides of the pool's length and width, making the overall dimensions 40+2w40 + 2w and 30+2w30 + 2w. The area of the deck alone is the total area minus the pool's area. Solving the algebraic equation (40+2w)(30+2w)−1200=296(40 + 2w)(30 + 2w) - 1200 = 296 yields a positive root of w=2w = 2.

Adım Adım Çözüm

1
Calculate the area of the pool.
40×30=120040 \times 30 = 1200 square feet.
You need the baseline area of the inner rectangle before the deck is added.
2
Write algebraic expressions for the outer dimensions of the pool and deck combined.
Length =40+2w= 40 + 2w, Width =30+2w= 30 + 2w.
The deck has a uniform width ww, which adds to both the top/bottom and left/right sides of the pool.
3
Formulate an equation for the area of the deck.
(40+2w)(30+2w)−1200=296(40 + 2w)(30 + 2w) - 1200 = 296.
The area of the deck alone is equal to the total area (pool plus deck) minus the area of the pool.
4
Expand the binomials and simplify into a standard quadratic equation.
1200+140w+4w2−1200=296  ⟹  4w2+140w−296=01200 + 140w + 4w^2 - 1200 = 296 \implies 4w^2 + 140w - 296 = 0.
Standard quadratic form (ax2+bx+c=0ax^2 + bx + c = 0) is required to solve for the unknown variable ww.
5
Solve the quadratic equation for ww.
Divide by 44 to get w2+35w−74=0w^2 + 35w - 74 = 0. Factoring yields (w+37)(w−2)=0(w + 37)(w - 2) = 0, so w=2w = 2.
Finding the positive root gives the actual physical width of the concrete deck.

Anahtar Kavram

Calculating the area of composite rectangular figures and solving quadratic equations derived from expanding geometric boundaries.
Soru 4Soru →

An automated lawn sprinkler rotates through an angle of 120∘120^\circ and sprays water outward to a maximum distance of 1818 feet. Which of the following represents the total area of the lawn covered by this sprinkler? (Leave your answer in terms of π\pi.)

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Cevap: 108π sq ft108\pi \text{ sq ft}

Cevap

108π sq ft108\pi \text{ sq ft}
The sprinkler covers a sector of a circle. The radius of this circle is the maximum spray distance, which is 1818 feet. The full area of a circle with this radius would be π(18)2=324π\pi(18)^2 = 324\pi square feet. Since the sprinkler rotates 120∘120^\circ, which is 120360\frac{120}{360} or 13\frac{1}{3} of a full circle, the covered area is 13\frac{1}{3} of 324π324\pi, resulting in 108π108\pi square feet.

Adım Adım Çözüm

1
Identify the geometric shape and the relevant area formula.
The area covered by the sprinkler is a sector of a circle. The formula for the area of a sector is Area=θ360∘×πr2Area = \frac{\theta}{360^\circ} \times \pi r^2.
The sprinkler covers a fractional portion of a full circle defined by its rotation angle.
2
Determine the fraction of the circle covered.
120∘360∘=13\frac{120^\circ}{360^\circ} = \frac{1}{3}
The sprinkler rotates 120∘120^\circ out of a total possible 360∘360^\circ for a complete circle.
3
Substitute the radius into the formula and solve.
13×π×(18)2=13×π×324=108π\frac{1}{3} \times \pi \times (18)^2 = \frac{1}{3} \times \pi \times 324 = 108\pi
The maximum spray distance (1818 feet) is the radius. Squaring 1818 gives 324324, and finding one-third of this yields the sector's area.

Anahtar Kavram

Area of a Circular Sector
Soru 5Soru →

A stained glass artist cuts a piece of glass into the shape of a right triangle. The two perpendicular legs of the triangle measure 3030 centimeters and 4040 centimeters. What is the total perimeter of this glass triangle in centimeters?

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Cevap: 120

Cevap

120
The correct answer is found by first determining the length of the hypotenuse using the Pythagorean theorem. Since the legs are 3030 and 4040, the hypotenuse is 302+402=2500=50\sqrt{30^2 + 40^2} = \sqrt{2500} = 50. The perimeter is then calculated by adding the lengths of all three sides: 30+40+50=12030 + 40 + 50 = 120.

Adım Adım Çözüm

1
Use the Pythagorean theorem to find the length of the missing hypotenuse.
c=302+402=900+1600=2500=50c = \sqrt{30^2 + 40^2} = \sqrt{900 + 1600} = \sqrt{2500} = 50 centimeters.
The perimeter requires all three side lengths, but only the two legs are provided.
2
Calculate the total perimeter of the right triangle.
Perimeter = 30+40+50=12030 + 40 + 50 = 120 centimeters.
The perimeter is the total distance around the outside of the shape, found by summing all side lengths.

Anahtar Kavram

Applying the Pythagorean theorem to find a missing side length, then using all three side lengths to calculate the perimeter of a right triangle.
Soru 6Soru →

Determine the required dimensions for the construction project.

Aşağıdaki boşlukları doldurun

A construction crew is building a wooden ramp with a right triangular cross-section. The horizontal base of the ramp measures 24 feet24\text{ feet} and it rises to a vertical height of 7 feet7\text{ feet}. According to the Pythagorean Theorem, the length of the sloped surface is feet, and the total perimeter of the ramp's triangular profile is feet.
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Cevap

The sloped surface is 25 feet, and the total perimeter is 56 feet.
The sloped surface corresponds to the hypotenuse of a right triangle with legs of 77 and 2424 feet. Applying the Pythagorean Theorem, 72+242=49+576=6257^2 + 24^2 = 49 + 576 = 625. Taking the square root of 625625 gives 25 feet25\text{ feet} for the sloped surface. The total perimeter is the sum of the base, height, and sloped surface: 24+7+25=56 feet24 + 7 + 25 = 56\text{ feet}.

Adım Adım Çözüm

1
Identify the known sides of the right triangle.
The legs of the right triangle are a=7a = 7 and b=24b = 24.
The horizontal base and vertical height form the two legs that intersect at a right angle.
2
Apply the Pythagorean Theorem to find the length of the hypotenuse.
c2=72+242=49+576=625c^2 = 7^2 + 24^2 = 49 + 576 = 625. Therefore, c=625=25c = \sqrt{625} = 25.
The sloped surface represents the hypotenuse (cc) of the right triangle.
3
Calculate the perimeter of the triangle.
7+24+25=567 + 24 + 25 = 56.
The perimeter is found by summing the lengths of all three sides of the triangular cross-section.

Anahtar Kavram

Using the Pythagorean Theorem to find the hypotenuse of a right triangle, and applying it to calculate the perimeter.
Soru 7Soru →

What is the measure of one interior angle of a regular octagon?

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Cevap: 135∘135^\circ

Cevap

The measure of one interior angle of a regular octagon is 135∘135^\circ.
To find a single interior angle of a regular polygon, use the formula (n−2)×180∘n\frac{(n - 2) \times 180^\circ}{n}. Substituting n=8n = 8 for an octagon gives 6×180∘8=1080∘8=135∘\frac{6 \times 180^\circ}{8} = \frac{1080^\circ}{8} = 135^\circ.

Adım Adım Çözüm

1
Identify the number of sides (nn) for an octagon.
n=8n = 8
An octagon is a polygon with 8 sides.
2
Calculate the total sum of the interior angles using the formula (n−2)×180∘(n - 2) \times 180^\circ.
(8−2)×180∘=6×180∘=1080∘(8 - 2) \times 180^\circ = 6 \times 180^\circ = 1080^\circ
This formula determines the combined measure of all interior angles for any polygon.
3
Divide the total sum by the number of sides to find the measure of a single angle.
1080∘÷8=135∘1080^\circ \div 8 = 135^\circ
In a regular polygon, all interior angles are equal, so dividing the total sum by the number of angles gives the measure of one.

Anahtar Kavram

Interior Angles of Regular Polygons
Soru 8Soru →

The interior angles of a quadrilateral are represented by the algebraic expressions 2x∘2x^\circ, (3x−15)∘(3x - 15)^\circ, (x+25)∘(x + 25)^\circ, and (2x+30)∘(2x + 30)^\circ. What is the measure of the largest angle in this quadrilateral?

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Cevap: 110∘110^\circ

Cevap

The largest angle measures 110∘110^\circ.
The interior angles of a quadrilateral must sum to 360∘360^\circ. By adding the four expressions together, we get 8x+40=3608x + 40 = 360. Solving for xx yields x=40x = 40. To find the largest angle, we substitute 4040 back into the original expressions: 2(40)=80∘2(40) = 80^\circ, 3(40)−15=105∘3(40) - 15 = 105^\circ, 40+25=65∘40 + 25 = 65^\circ, and 2(40)+30=110∘2(40) + 30 = 110^\circ. Comparing these four values, 110∘110^\circ is the largest.

Adım Adım Çözüm

1
Set up an equation based on the sum of interior angles.
2x+(3x−15)+(x+25)+(2x+30)=3602x + (3x - 15) + (x + 25) + (2x + 30) = 360
The sum of the interior angles of any quadrilateral is always 360∘360^\circ.
2
Combine the like terms on the left side of the equation.
8x+40=3608x + 40 = 360
Grouping the xx terms (2x+3x+x+2x=8x2x + 3x + x + 2x = 8x) and constant terms (−15+25+30=40-15 + 25 + 30 = 40) simplifies the algebraic expression.
3
Solve for the variable xx.
8x=3208x = 320, which means x=40x = 40.
Subtracting 40 from both sides and then dividing by 8 isolates xx.
4
Substitute x=40x = 40 into each of the original expressions to determine the measure of each angle.
The angles are 2(40)=80∘2(40) = 80^\circ; 3(40)−15=105∘3(40) - 15 = 105^\circ; 40+25=65∘40 + 25 = 65^\circ; and 2(40)+30=110∘2(40) + 30 = 110^\circ.
The value of xx alone does not answer the question; the specific angle measures must be evaluated.
5
Identify the largest value among the calculated angles.
The largest value is 110∘110^\circ.
The question specifically asks for the maximum angle measure in the quadrilateral.

Anahtar Kavram

The sum of the interior angles of a quadrilateral is always 360 degrees. Algebraic substitution is required to convert variable expressions back into geometric measurements.
Tahmini Süre:1m 30s
Soru 9Soru →

Match each polygon or quadrilateral with its defining geometric property.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Parallelogram
Trapezoid
Rhombus
Hexagon

Eşleşmeler

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Cevap

Parallelogram matches with 'two pairs of parallel opposite sides', Trapezoid matches with 'exactly one pair of parallel sides', Rhombus matches with 'four sides of equal length', and Hexagon matches with 'exactly six sides'.
Each shape is matched to its fundamental geometric definition based on the number of sides, side lengths, and parallel properties. Knowing these core definitions is essential for classifying polygons and quadrilaterals correctly.

Adım Adım Çözüm

1
Analyze the properties of a parallelogram.
It has two pairs of parallel opposite sides.
This is the fundamental geometric definition of a parallelogram.
2
Analyze the properties of a trapezoid.
It is defined by having exactly one pair of parallel sides.
This distinguishes a trapezoid from other quadrilaterals like parallelograms.
3
Analyze the properties of a rhombus.
It is a quadrilateral where all four sides are of equal length.
While it also has parallel sides, the equal side lengths are its distinguishing feature.
4
Identify the number of sides for a hexagon.
A hexagon is a polygon with exactly six sides.
The prefix 'hexa-' denotes six in geometry.

Anahtar Kavram

Basic Properties of Quadrilaterals and Polygons
Soru 10Soru →

A decorative floor tile is manufactured in the shape of a regular pentagon. What is the degree measure of each interior angle of the tile?

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Cevap: 108∘108^\circ

Cevap

108∘108^\circ
The interior angles of an nn-sided polygon sum to (n−2)×180∘(n - 2) \times 180^\circ. For a 5-sided pentagon, the sum is (5−2)×180∘=540∘(5 - 2) \times 180^\circ = 540^\circ. Since the tile is a regular pentagon, all five angles are identical. Dividing the total 540∘540^\circ by 5 yields exactly 108∘108^\circ per corner.

Adım Adım Çözüm

1
Identify the number of sides in a regular pentagon.
n=5n = 5
A pentagon is defined as a geometric polygon with exactly 5 sides.
2
Calculate the sum of all interior angles using the polygon formula (n−2)×180∘(n - 2) \times 180^\circ.
(5−2)×180∘=3×180∘=540∘(5 - 2) \times 180^\circ = 3 \times 180^\circ = 540^\circ
This formula determines the total degree measure for the interior angles of any convex polygon.
3
Divide the total sum by the number of sides to find the measure of a single interior angle.
540∘÷5=108∘540^\circ \div 5 = 108^\circ
Because it is a regular pentagon, all interior angles are equal in measure.

Anahtar Kavram

Interior Angles of Regular Polygons
Soru 11Soru →

Match each quadrilateral with its precise geometric defining properties.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Rhombus
Rectangle
Kite
Isosceles Trapezoid

Eşleşmeler

Cevabı ve açıklamayı göster

Cevap

Rhombus matches the parallelogram with perpendicular diagonals that bisect angles. Rectangle matches the parallelogram with four right angles. Kite matches the quadrilateral with consecutive congruent sides. Isosceles Trapezoid matches the quadrilateral with exactly one pair of parallel sides.
Each quadrilateral has unique defining traits involving their sides, angles, and diagonals. A rhombus requires perpendicular diagonals and parallel opposite sides. A rectangle requires right angles and congruent diagonals. A kite requires adjacent equal sides and perpendicular diagonals. An isosceles trapezoid requires exactly one pair of parallel sides and congruent diagonals.

Adım Adım Çözüm

1
Analyze the unique properties of a Rhombus.
It is a parallelogram with all equal sides, which leads to perpendicular diagonals that bisect the opposite angles.
To distinguish it from other standard parallelograms like rectangles.
2
Analyze the unique properties of a Rectangle.
It has four right angles and, unlike a standard parallelogram, has diagonals that are identical in length.
To correctly identify the item describing congruent diagonals in a parallelogram.
3
Analyze the unique properties of a Kite.
It has adjacent sides that are equal (consecutive congruent sides), which forces the diagonals to meet at 90 degrees.
To match it with the correct non-parallelogram definition.
4
Analyze the unique properties of an Isosceles Trapezoid.
It has exactly one pair of parallel sides (bases) and the symmetry from equal non-parallel sides creates equal diagonals.
To differentiate it from general trapezoids and generic parallelograms.

Anahtar Kavram

Quadrilaterals and Polygons
Soru 12Soru →

A land surveyor is measuring a four-sided plot of land. They record three of the interior angles as 78∘78^\circ, 104∘104^\circ, and 83∘83^\circ. What is the measure of the fourth interior angle, in degrees?

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Cevap: 95

Cevap

The fourth interior angle measures 95∘95^\circ.
The correct answer is found by subtracting the sum of the three known angles (265∘265^\circ) from the total interior angle sum of a quadrilateral (360∘360^\circ), which yields 95∘95^\circ.

Adım Adım Çözüm

1
Identify the total sum of interior angles for a quadrilateral.
360∘360^\circ
A quadrilateral has 4 sides, and the sum of interior angles is calculated as (n−2)×180∘(n - 2) \times 180^\circ. For n=4n = 4, this is 2×180∘=360∘2 \times 180^\circ = 360^\circ.
2
Calculate the sum of the three given angles.
78∘+104∘+83∘=265∘78^\circ + 104^\circ + 83^\circ = 265^\circ
To find the missing part, we must first determine the combined total of the known angles.
3
Subtract the sum of the given angles from the total quadrilateral angle sum.
360∘−265∘=95∘360^\circ - 265^\circ = 95^\circ
The remaining amount represents the exact measure of the fourth interior angle.

Anahtar Kavram

The sum of the interior angles of any convex quadrilateral is always exactly 360∘360^\circ.
Soru 13Soru →

A rectangular room has a length of 1212 feet and a width of 1010 feet. What is the perimeter of the room?

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Cevap: 4444 feet

Cevap

4444 feet
The perimeter is the total distance around the boundary of the rectangle. Since a rectangle has two equal lengths and two equal widths, the perimeter is 2×12+2×10=24+20=442 \times 12 + 2 \times 10 = 24 + 20 = 44 feet.

Adım Adım Çözüm

1
Identify the formula for the perimeter of a rectangle.
P=2×(Length+Width)P = 2 \times (\text{Length} + \text{Width}) or P=2L+2WP = 2L + 2W
The perimeter is the total distance around the outside of the shape, which includes two lengths and two widths.
2
Substitute the given dimensions into the formula.
P=2×(12+10)P = 2 \times (12 + 10)
The length is given as 1212 feet and the width is 1010 feet.
3
Calculate the final perimeter.
P=2×22=44P = 2 \times 22 = 44
Performing the addition inside the parentheses first, then multiplying by 22 yields the total distance.

Anahtar Kavram

The perimeter of a rectangle is the total distance around its edges, calculated as twice the sum of its length and width.
Tahmini Süre:45s
Soru 14Soru →

In a parallelogram, the measure of one interior angle is 30∘30^\circ less than twice the measure of the consecutive interior angle. What is the measure of the larger angle?

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Cevap: 110∘110^\circ

Cevap

The measure of the larger angle is 110∘110^\circ.
The correct answer correctly identifies that consecutive angles in a parallelogram are supplementary. Setting up the equation x+(2x−30)=180∘x + (2x - 30) = 180^\circ and solving for xx yields 70∘70^\circ. Substituting this back into the expression for the larger angle gives 2(70)−30=110∘2(70) - 30 = 110^\circ.

Adım Adım Çözüm

1
Identify the geometric property relating the angles.
Consecutive interior angles of a parallelogram are supplementary, meaning they add up to 180∘180^\circ.
This is a fundamental property of parallelograms formed by parallel lines cut by a transversal.
2
Translate the word problem into an algebraic equation.
Let the smaller angle be xx. The larger angle is 2x−302x - 30. Therefore, x+(2x−30)=180x + (2x - 30) = 180.
This captures both the relationship described ('30∘30^\circ less than twice') and the supplementary geometric property.
3
Solve the algebraic equation for xx.
Combine terms: 3x−30=1803x - 30 = 180. Add 3030 to both sides: 3x=2103x = 210. Divide by 33: x=70∘x = 70^\circ.
Isolating the variable determines the exact measure of the smaller angle.
4
Calculate the measure of the larger angle.
2(70)−30=140−30=110∘2(70) - 30 = 140 - 30 = 110^\circ.
The question specifically asks for the measure of the larger angle, not the smaller one.

Anahtar Kavram

Properties of Parallelograms and Algebraic Translation

Alternatif Yöntem

You can solve this by testing the answer choices. If the larger angle is 110∘110^\circ, the smaller consecutive angle must be 180∘−110∘=70∘180^\circ - 110^\circ = 70^\circ. Check if 110∘110^\circ is 30∘30^\circ less than twice 70∘70^\circ: 2(70)−30=140−30=110∘2(70) - 30 = 140 - 30 = 110^\circ. The values perfectly match the problem statement.
Tahmini Süre:1m 15s
Soru 15Soru →

A triangular pennant has a base of 88 inches and a height of 1515 inches. What is the area of the pennant, in square inches?

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Cevap: 60

Cevap

60
The correct area is found by multiplying the base by the height, and then dividing by two according to the standard triangle area formula.

Adım Adım Çözüm

1
Identify the formula for the area of a triangle.
A=12bhA = \frac{1}{2}bh
The object is described as a triangular pennant.
2
Substitute the given base and height into the formula.
A=12(8)(15)A = \frac{1}{2}(8)(15)
The base is given as 88 inches and the height is 1515 inches.
3
Calculate the final product.
6060
Multiplying the terms: 12×8=4\frac{1}{2} \times 8 = 4, and 4×15=604 \times 15 = 60.

Anahtar Kavram

Area of a Triangle
Tahmini Süre:45s
Soru 16Soru →

The sum of the interior angles of a convex polygon is exactly three times the sum of its exterior angles. How many sides does this polygon have?

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Cevap: 8

Cevap

8
Applying the core polygon properties, the interior angle sum is 180∘(n−2)180^\circ(n - 2) and the exterior angle sum is 360∘360^\circ. Setting 180∘(n−2)=3(360∘)180^\circ(n - 2) = 3(360^\circ) and solving for nn yields 8.

Adım Adım Çözüm

1
Identify the interior angle sum formula.
Sum = 180∘(n−2)180^\circ(n - 2)
This formula provides the total sum of all interior angles for an nn-sided polygon.
2
Identify the exterior angle sum property.
Sum = 360∘360^\circ
A fundamental property of all convex polygons is that the sum of their exterior angles is exactly 360∘360^\circ.
3
Set up the algebraic equation.
180∘(n−2)=3×360∘180^\circ(n - 2) = 3 \times 360^\circ
The question states the interior sum is exactly three times the exterior sum.
4
Solve the equation for nn.
n=8n = 8
Dividing 1080∘1080^\circ by 180∘180^\circ yields 6, and adding 2 gives a final side count of 8.

Anahtar Kavram

Polygon Angle Sum Theorems
Soru 17Soru →

A circular target has a diameter of 1616 inches. Which of the following represents the area of the target, in square inches?

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Cevap: 64π64\pi

Cevap

64π64\pi
The correct answer accurately divides the diameter of 1616 inches by 22 to find the radius of 88 inches. It then squares the radius (82=648^2 = 64) and multiplies by π\pi to find the area of 64π64\pi square inches.

Adım Adım Çözüm

1
Find the radius of the circle.
r=16/2=8r = 16 / 2 = 8 inches
The area formula requires the radius, which is exactly half of the diameter.
2
Apply the area formula for a circle (A=πr2A = \pi r^2).
A=π(8)2A = \pi(8)^2
Substituting the calculated radius into the standard area formula.
3
Simplify the expression.
A=64πA = 64\pi square inches
Squaring the radius (8×8=648 \times 8 = 64) provides the final area in terms of π\pi.

Anahtar Kavram

The area of a circle is found using the formula A=πr2A = \pi r^2. When given the diameter, it must first be divided by 2 to find the radius.
Soru 18Soru →

Two parallel lines, L1L_1 and L2L_2, are intersected by three distinct transversals. The first transversal creates a pair of alternate interior angles that measure (4x−3y)∘(4x - 3y)^\circ and (2x+y)∘(2x + y)^\circ. The second transversal creates a pair of consecutive (same-side) interior angles that measure (3x+y)∘(3x + y)^\circ and (5y+36)∘(5y + 36)^\circ. The third transversal creates a pair of corresponding angles. One of these corresponding angles measures (x+y+z)∘(x + y + z)^\circ, and the angle forming a linear pair with it measures 108∘108^\circ. What is the value of zz?

Cevabı ve açıklamayı göster

Cevap: 36

Cevap

36
By applying geometric theorems for transversals (alternate interior angles are equal, same-side interior angles sum to 180), a system of equations reveals x = 24 and y = 12. Using the linear pair property, the final angle expression (x + y + z) equals 72, which isolates z to exactly 36.

Adım Adım Çözüm

1
Set up an equation using the alternate interior angles.
4x−3y=2x+y⇒2x=4y⇒x=2y4x - 3y = 2x + y \Rightarrow 2x = 4y \Rightarrow x = 2y
Alternate interior angles formed by a transversal intersecting parallel lines are equal.
2
Set up an equation using the consecutive (same-side) interior angles.
(3x+y)+(5y+36)=180⇒3x+6y+36=180⇒3x+6y=144(3x + y) + (5y + 36) = 180 \Rightarrow 3x + 6y + 36 = 180 \Rightarrow 3x + 6y = 144
Consecutive interior angles formed by a transversal intersecting parallel lines are supplementary (sum to 180 degrees).
3
Solve the system of equations by substituting x=2yx = 2y into the second equation.
3(2y)+6y=144⇒6y+6y=144⇒12y=144⇒y=123(2y) + 6y = 144 \Rightarrow 6y + 6y = 144 \Rightarrow 12y = 144 \Rightarrow y = 12. Since x=2yx = 2y, x=24x = 24.
Substitution efficiently solves a two-variable linear system to find the individual angle components.
4
Use the linear pair to determine the measure of the corresponding angle, then solve for zz.
(x+y+z)=180−108=72(x + y + z) = 180 - 108 = 72. Substituting known values: 24+12+z=72⇒36+z=72⇒z=3624 + 12 + z = 72 \Rightarrow 36 + z = 72 \Rightarrow z = 36.
Angles forming a linear pair are supplementary. Finding the target angle allows substitution of xx and yy to isolate zz.

Anahtar Kavram

Complex systems of transversal angle relationships (alternate interior, consecutive interior, linear pairs)
Tahmini Süre:3m 0s
Soru 19Soru →

A convex hexagon has five interior angles that measure 120∘120^\circ, 135∘135^\circ, 115∘115^\circ, 140∘140^\circ, and 110∘110^\circ. If the measure of the sixth interior angle is represented by the algebraic expression (4x+16)∘(4x + 16)^\circ, what is the value of xx?

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Cevap: 2121

Cevap

The correct answer is 2121.
The sum of the interior angles of a hexagon (66 sides) is (6−2)×180∘=720∘(6 - 2) \times 180^\circ = 720^\circ. The five given angles add up to 620∘620^\circ. This means the sixth angle must be 720∘−620∘=100∘720^\circ - 620^\circ = 100^\circ. Setting the algebraic expression 4x+164x + 16 equal to 100100 and solving for xx by subtracting 1616 and dividing by 44 gives x=21x = 21.

Adım Adım Çözüm

1
Calculate the sum of the interior angles of a convex hexagon.
The sum is (6−2)×180∘=720∘(6 - 2) \times 180^\circ = 720^\circ.
The formula for the sum of interior angles is (n−2)×180∘(n - 2) \times 180^\circ, where nn is the number of sides. A hexagon has 66 sides.
2
Find the sum of the five given angles.
120∘+135∘+115∘+140∘+110∘=620∘120^\circ + 135^\circ + 115^\circ + 140^\circ + 110^\circ = 620^\circ.
Adding the known angles allows us to find the combined measure of the known portion of the polygon.
3
Calculate the measure of the sixth angle.
720∘−620∘=100∘720^\circ - 620^\circ = 100^\circ.
Subtracting the sum of the five known angles from the total sum gives the measure of the missing angle.
4
Set up and solve the equation for xx.
4x+16=100  ⟹  4x=84  ⟹  x=214x + 16 = 100 \implies 4x = 84 \implies x = 21.
The sixth angle is represented by the expression (4x+16)∘(4x + 16)^\circ, so setting it equal to 100100 allows us to isolate and solve for xx.

Anahtar Kavram

Polygon Interior Angles and Linear Equations
Soru 20Soru →

The perimeter of a square courtyard is 3636 meters. What is the area of the courtyard, in square meters?

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Cevap: 81

Cevap

81
A square has four sides of equal length. Given a perimeter of 3636 meters, each side measures 36÷4=936 \div 4 = 9 meters. The area of a square is its side length squared, which is 92=819^2 = 81 square meters.

Adım Adım Çözüm

1
Find the length of one side of the square.
36÷4=936 \div 4 = 9 meters.
The perimeter of a square is the sum of its four equal sides, so dividing the total perimeter by 4 gives the length of a single side.
2
Calculate the area of the square.
9×9=819 \times 9 = 81 square meters.
The area of a square is calculated by squaring the length of one of its sides (A=s2A = s^2).

Anahtar Kavram

Perimeter and Area of 2D Figures
Sayfa 1 / 8Sonraki