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Amy Ferguson Moncure

SAT · Geometry and Trigonometry

Geometry – Area of 2D Shapes

Find the area of rectangles, squares, triangles, and circles, and use V = Bh to find the area of a base.

SAT formula sheet

Rectangle A = ℓwTriangle A = 12 bhCircle A = πr²Circumference C = 2πr

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SAT Suite Question Bank

Official SAT Area of 2D Shapes Items

Search each Question ID at satsuitequestionbank.collegeboard.org under Geometry and Trigonometry, skill Area and volume, for the full stem, choices, and rationale.

Question ID Difficulty Topic Focus
0e40dfb0 ⭐ Easy Area of rectangle
165c30c4 ⭐ Easy Area of rectangle
3453aafc ⭐ Easy Area of rectangle
4420e500 ⭐ Easy Area of rectangle
4efea6a3 ⭐ Easy Given area of rectangle, find length
5252e606 ⭐ Easy Area of square
575f1e12 ⭐ Easy Area of rectangle
59cb654c ⭐ Easy Given area of square, find length
689abc2a ⭐ Easy Area of rectangle − area of square
93f48423 ⭐ Easy Area of rectangle
9d2e7037 ⭐ Easy Area of rectangle
a490003a ⭐⭐ Easy Area of rectangle where the length is # more than the width
c88183f7 ⭐ Easy Perimeter of rectangle
d2047497 ⭐ Easy Area of rectangle
f39f88b7 ⭐ Easy Area of a triangle
f60bb551 ⭐ Easy Find width of rectangle given area and length
08b7a3f5 ⭐⭐ Medium Given volume of a triangular prism as Bh, the volume and height of the prism, find the area.
096c7ef5 ⭐⭐⭐ Medium Find the diameter of a circle given three points on a graph.
468613c0 ⭐ Medium Area of a triangle
5afbdc8e ⭐⭐⭐ Medium Find the side length of a square given the area. Need more help with this idea?
6ae1360d ⭐⭐ Medium Area of a circle
96467fea ⭐⭐ Medium Area of two circles, where students are given the area of one circle in terms of π and have to calculate the area of the other circle
98c12e38 ⭐⭐ Medium Area of two circles, where students are given the area of one circle in terms of π and have to calculate the area of the other circle
9c0a0eca ⭐ Medium Area of a triangle
a4ed5285 ⭐ Medium Area of a triangle
aef4fd8a ⭐⭐ Medium Expression for area of a square
c4e5e23c ⭐⭐⭐ Medium Find the area of a square, given the area of another square and how the length is related to the other square.
e86f0651 ⭐⭐ Medium Area of a circle in terms of π given radius
099526fc ⭐⭐⭐⭐ Hard Given area of a triangle and a side length, find the height. Contains radicals. This is a great problem!!
306264ab ⭐⭐⭐⭐ Hard Given three side lengths of a right triangle, find the area. Remember, the hypotenuse is the longest side. This is a great problem!
eb70d2d0 ⭐⭐⭐⭐⭐ Hard Area of non-right triangle, given three points, inscribe the triangle into a rectangle

Tip: Search these exact Question IDs in the College Board SAT Suite Question Bank, Geometry and Trigonometry, skill Area and volume for full questions and rationales.

Easy

Review

Area and perimeter from the formula sheet.

1

A rectangle is 11 cm long and 6 cm wide. What is the area?

Show Answer

A = ℓw

A = 11 × 6

A = 66

Answer: 66 square centimeters

2

A rectangle is 14 feet long and 5 feet wide. What is the perimeter?

Show Answer

P = 2ℓ + 2w

P = 2(14) + 2(5)

P = 28 + 10

P = 38

Answer: 38 feet

3

A square has a side length of 7 inches. What is the area?

Show Answer

A = s²

A = 7²

A = 49

Answer: 49 square inches

4

A triangle has a base of 14 meters and a height of 6 meters. What is the area?

Show Answer

A = 12bh

A = 12 × 14 × 6

A = 42

Answer: 42 square meters

5

A circle has a radius of 5. What is the area? Leave the answer in terms of π.

Show Answer

A = πr²

A = π(5)²

A = 25π

Answer: 25π

6

A rectangle has an area of 54 and a length of 9. What is the width?

Show Answer

A = ℓw

54 = 9 × w

w = 6

Answer: 6

7

A right triangle has side lengths 20, 21, and 29. Find the area.

Show Answer

The longest side is the hypotenuse.

20² = 400

21² = 441

29² = 841

400 + 441 = 841, so 29 is the hypotenuse. The legs are 20 and 21.

A = 12bh

A = 12 × 20 × 21

A = 210

Answer: 210

8

A triangle has area 56 and a base of 14. The height is a whole number. Find the height.

Show Answer

A = 12bh

56 = 12 × 14 × h

56 = 7h

h = 8

Answer: 8

Medium

V = Bh

The volume and the height are given. Find the area of the base. Each solid is different.

1

A right rectangular prism has a volume of 192 cubic inches. The height is 8 inches. What is the area of the base?

Show Answer

V = Bh

192 = B × 8

B = 24

Answer: 24 square inches

2

A right triangular prism has a volume of 150 cubic centimeters. The height is 10 centimeters. What is the area of the base?

Show Answer

V = Bh

150 = B × 10

B = 15

Answer: 15 square centimeters

3

A right cylinder has a volume of 63π cubic feet. The height is 7 feet. What is the area of the base?

Show Answer

V = Bh

63π = B × 7

B = 9π

Answer: 9π square feet

Medium

Inscribed Triangles

The diameter is the horizontal or vertical side. Count it on the grid. Give the answer in terms of π and as a decimal to two places.

1

Triangle ABC is inscribed in a circle. The vertices are A(1, 2), B(9, 2), and C(5, 6). Find the circumference of the circle.

0123456789101234567ABC
Show Answer
012345678910-3-2-101234567ABC

AB is horizontal. Count that side. It is a diameter.

The diameter is 8.

The radius is half the diameter.

r = 82

r = 4

C = 2πr

C = 2π(4)

C = 8π

8π ≈ 25.13

Answer: 8π or 25.13

2

Triangle ABC is inscribed in a circle. The vertices are A(2, 1), B(2, 7), and C(5, 4). Find the area of the circle.

123456012345678ABC
Show Answer
-2-10123456012345678ABC

AB is vertical. Count that side. It is a diameter.

The diameter is 6.

The radius is half the diameter.

r = 62

r = 3

A = πr²

A = π(3)²

A = 9π

9π ≈ 28.27

Answer: 9π or 28.27

3

Triangle ABC is inscribed in a circle. The vertices are A(1, 4), B(11, 4), and C(6, 9). Find the circumference of the circle.

0123456789101112345678910ABC
Show Answer
0123456789101112-2-1012345678910ABC

AB is horizontal. Count that side. It is a diameter.

The diameter is 10.

The radius is half the diameter.

r = 102

r = 5

C = 2πr

C = 2π(5)

C = 10π

10π ≈ 31.42

Answer: 10π or 31.42

Medium

Area of Triangle

The side lengths are simplified radicals. Decide which side is the hypotenuse before you use the area formula.

1

A right triangle has side lengths 2square root of 7, 2square root of 3, and 4. Find the area.

Show Answer

Square each side. The greatest square belongs to the hypotenuse.

(2square root of 7)2 = 2² × 7

= 4 × 7

= 28

(2square root of 3)2 = 2² × 3

= 4 × 3

= 12

4² = 16

12 + 16 = 28, so 2square root of 7 is the hypotenuse.

The legs are 2square root of 3 and 4.

A = 12bh

A = 12 × 2square root of 3 × 4

A = 4square root of 3

Answer: 4square root of 3

2

A right triangle has side lengths 6, 3square root of 6, and 3square root of 2. Find the area.

Show Answer

Square each side. The greatest square belongs to the hypotenuse.

6² = 36

(3square root of 6)2 = 3² × 6

= 9 × 6

= 54

(3square root of 2)2 = 3² × 2

= 9 × 2

= 18

36 + 18 = 54, so 3square root of 6 is the hypotenuse.

The legs are 6 and 3square root of 2.

A = 12bh

A = 12 × 6 × 3square root of 2

A = 9square root of 2

Answer: 9square root of 2

3

A right triangle has side lengths square root of 65, 2square root of 5, and 3square root of 5. Find the area.

Show Answer

Square each side. The greatest square belongs to the hypotenuse.

(square root of 65)2 = 65

(2square root of 5)2 = 2² × 5

= 4 × 5

= 20

(3square root of 5)2 = 3² × 5

= 9 × 5

= 45

20 + 45 = 65, so square root of 65 is the hypotenuse.

The legs are 2square root of 5 and 3square root of 5.

A = 12bh

A = 12 × 2square root of 5 × 3square root of 5

A = 3 × 5

A = 15

Answer: 15

4

A right triangle has side lengths 3square root of 2, square root of 26, and 2square root of 2. Find the area.

Show Answer

Square each side. The greatest square belongs to the hypotenuse.

(3square root of 2)2 = 3² × 2

= 9 × 2

= 18

(square root of 26)2 = 26

(2square root of 2)2 = 2² × 2

= 4 × 2

= 8

18 + 8 = 26, so square root of 26 is the hypotenuse.

The legs are 3square root of 2 and 2square root of 2.

A = 12bh

A = 12 × 3square root of 2 × 2square root of 2

A = 3 × 2

A = 6

Answer: 6

5

A right triangle has side lengths 2square root of 10, 5square root of 2, and 3square root of 10. Find the area.

Show Answer

Square each side. The greatest square belongs to the hypotenuse.

(2square root of 10)2 = 2² × 10

= 4 × 10

= 40

(5square root of 2)2 = 5² × 2

= 25 × 2

= 50

(3square root of 10)2 = 3² × 10

= 9 × 10

= 90

40 + 50 = 90, so 3square root of 10 is the hypotenuse.

The legs are 2square root of 10 and 5square root of 2.

A = 12bh

A = 12 × 2square root of 10 × 5square root of 2

A = 5square root of 20

square root of 20 = square root of 4 × square root of 5

= 2square root of 5

A = 5 × 2square root of 5

A = 10square root of 5

Answer: 10square root of 5

Hard

Area of Non-Right Triangle

Inscribe the triangle in a rectangle. Subtract the three right triangles in the corners.

Example

A triangle has vertices A(2, 1), B(8, 3), and C(5, 7). Find the area.

123456789012345678ABC

Draw a rectangle around the triangle. Each side of the rectangle passes through the highest, lowest, leftmost, or rightmost vertex.

123456789012345678ABC

The width is 8 − 2 = 6.

The height is 7 − 1 = 6.

A = ℓw

A = 6 × 6

A = 36

Three right triangles fill the corners. Find each area.

Right angle at (8, 1). The legs are 6 and 2.

A = 12bh

A = 12 × 6 × 2

A = 6

Right angle at (8, 7). The legs are 3 and 4.

A = 12bh

A = 12 × 3 × 4

A = 6

Right angle at (2, 7). The legs are 3 and 6.

A = 12bh

A = 12 × 3 × 6

A = 9

Area of the triangle = area of the rectangle − the three right triangles.

36 − 6 − 6 − 9 = 15

Answer: 15

1

A triangle has vertices A(1, 4), B(7, 2), and C(3, 8). Find the area.

012345678123456789ABC
Show Answer

Draw a rectangle around the triangle. Each side of the rectangle passes through the highest, lowest, leftmost, or rightmost vertex.

012345678123456789ABC

The width is 7 − 1 = 6.

The height is 8 − 2 = 6.

A = ℓw

A = 6 × 6

A = 36

Three right triangles fill the corners. Find each area.

Right angle at (1, 2). The legs are 6 and 2.

A = 12bh

A = 12 × 6 × 2

A = 6

Right angle at (7, 8). The legs are 4 and 6.

A = 12bh

A = 12 × 4 × 6

A = 12

Right angle at (1, 8). The legs are 2 and 4.

A = 12bh

A = 12 × 2 × 4

A = 4

Area of the triangle = area of the rectangle − the three right triangles.

36 − 6 − 12 − 4 = 14

Answer: 14

2

A triangle has vertices A(2, 7), B(9, 5), and C(4, 1). Find the area.

12345678910012345678ABC
Show Answer

Draw a rectangle around the triangle. Each side of the rectangle passes through the highest, lowest, leftmost, or rightmost vertex.

12345678910012345678ABC

The width is 9 − 2 = 7.

The height is 7 − 1 = 6.

A = ℓw

A = 7 × 6

A = 42

Three right triangles fill the corners. Find each area.

Right angle at (9, 7). The legs are 7 and 2.

A = 12bh

A = 12 × 7 × 2

A = 7

Right angle at (9, 1). The legs are 5 and 4.

A = 12bh

A = 12 × 5 × 4

A = 10

Right angle at (2, 1). The legs are 2 and 6.

A = 12bh

A = 12 × 2 × 6

A = 6

Area of the triangle = area of the rectangle − the three right triangles.

42 − 7 − 10 − 6 = 19

Answer: 19

3

A triangle has vertices A(9, 8), B(1, 5), and C(5, 2). Find the area.

012345678910123456789ABC
Show Answer

Draw a rectangle around the triangle. Each side of the rectangle passes through the highest, lowest, leftmost, or rightmost vertex.

012345678910123456789ABC

The width is 9 − 1 = 8.

The height is 8 − 2 = 6.

A = ℓw

A = 8 × 6

A = 48

Three right triangles fill the corners. Find each area.

Right angle at (1, 8). The legs are 8 and 3.

A = 12bh

A = 12 × 8 × 3

A = 12

Right angle at (1, 2). The legs are 4 and 3.

A = 12bh

A = 12 × 4 × 3

A = 6

Right angle at (9, 2). The legs are 4 and 6.

A = 12bh

A = 12 × 4 × 6

A = 12

Area of the triangle = area of the rectangle − the three right triangles.

48 − 12 − 6 − 12 = 18

Answer: 18

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