Finding the Area of a Trapezoid by Decomposing - Cut Each Trapezoid into a Rectangle and Two Triangles to Find Its Area

Sep 30, 2026

Uploaded by Miles

Practice problems for finding the area of a trapezoid by decomposing it into a rectangle plus two triangles. Each item provides trapezoid dimensions (bases, height, and the widths of the left and right triangles) using different units such as feet, centimeters, meters, and inches. Multiple-choice answers are included for four labeled problems, with a separate answer key listing the correct areas for each case. Suitable for classroom use and assessment of area-of-trapezoid reasoning.

LanguageEnglish

CategoryExam

FormatPDF

Pages3

Reading Time8 min

AccessFree to download

Problem Set

Four Trapezoid Area Questions

Answer Key

Finding the Area of a Trapezoid by Decomposing Name: | Cut each trapezoid into a rectangle and two triangles to find its area. | | 1.
2.
3.
4. | Answers | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | | 1) 8 ft

16 ft
The height is 7 ft. The left triangle is 5 ft wide and the right triangle is 3 ft wide.
A. 112 ft²
B. 168 ft²
C. 56 ft²
D. 84 ft² | 2) 8 cm

19 cm
The height is 4 cm. The left triangle is 7 cm wide and the right triangle is 4 cm wide.
A. 76 cm²
B. 32 cm²
C. 108 cm²
D. 54 cm² | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 3) 8 m

21 m
The height is 6 m. The left triangle is 6 m wide and the right triangle is 7 m wide.
A. 48 m²
B. 87 m²
C. 126 m²
D. 174 m² | 4) 10 in

18 in
The height is 10 in. The left triangle is 6 in wide and the right triangle is 2 in wide.
A. 180 in²
B. 100 in²
C. 140 in²
D. 280 in² | | | | | | | | | | 1-4 | | 75 | 50 | 25 | 0 | [www.CommonCoreSheets.com](www.CommonCoreSheets.com) Math Finding the Area of a Trapezoid by Decomposing Name: Answer Key | Cut each trapezoid into a rectangle and two triangles to find its area. | | Answers 1. 84 ft² 2. 54 cm² 3. 87 m² 4. 140 in² | | --- | --- | --- | | 1) 8 ft

16 ft
The height is 7 ft. The left triangle is 5 ft wide and the right triangle is 3 ft wide.
A. 112 ft²
B. 168 ft²
C. 56 ft²
D. 84 ft² | 2) 8 cm

19 cm
The height is 4 cm. The left triangle is 7 cm wide and the right triangle is 4 cm wide.
A. 76 cm²
B. 32 cm²
C. 108 cm²
D. 54 cm² | | | 3) 8 m

21 m
The height is 6 m. The left triangle is 6 m wide and the right triangle is 7 m wide.
A. 48 m²
B. 87 m²
C. 126 m²
D. 174 m² | 4) 10 in

18 in
The height is 10 in. The left triangle is 6 in wide and the right triangle is 2 in wide.
A. 180 in²
B. 100 in²
C. 140 in²
D. 280 in² | | Math Seed: 20283817-1359 [www.CommonCoreSheets.com](www.CommonCoreSheets.com) 1-4 75 50 25 0 Finding the Area of a Trapezoid by Decomposing Name: | Cut each trapezoid into a rectangle and two triangles to find its area.
1) 8 ft

16 ft
The height is 7 ft. The left triangle is 5 ft wide and the right triangle is 3 ft wide.
A. 112 ft²
B. 168 ft²
C. 56 ft²
D. 84 ft²
2) 8 cm

19 cm
The height is 4 cm. The left triangle is 7 cm wide and the right triangle is 4 cm wide.
A. 76 cm²
B. 32 cm²
C. 108 cm²
D. 54 cm²
3) 8 m

21 m
The height is 6 m. The left triangle is 6 m wide and the right triangle is 7 m wide.
A. 48 m²
B. 87 m²
C. 126 m²
D. 174 m²
4) 10 in

18 in
The height is 10 in. The left triangle is 6 in wide and the right triangle is 2 in wide.
A. 180 in²
B. 100 in² | 1.
2.
3.
4. | Answers | | --- | --- | --- | | | | | | | | | | | | | | | | | Math Modified [www.CommonCoreSheets.com](www.CommonCoreSheets.com) 1-4 75 | | 50 | 25 | 0 | | --- | --- | --- | --- |

FAQs

How do you find a trapezoid’s area by decomposing it?

Cut the trapezoid into a rectangle and two triangles, then add the areas of those three shapes.

What information is given for each problem?

Each problem lists the trapezoid’s measurements, including the height and the triangle widths (left and right), plus the bases, to compute the rectangle and triangle areas.

Are the answers provided as choices?

Yes. Each question includes multiple-choice options, and the answer key provides the correct area for problems 1 through 4.

Sep 30, 2026

Uploaded by Miles