Area of Irregular Figures - Grade 9

This worksheet focuses on calculating the area of irregular figures by decomposing them into simpler geometric shapes.

Grade 9 Math GeometryArea of Irregular Figures

Use This Worksheet

Includes

3 Short AnswerFill in the BlanksTrue / FalseMultiple ChoiceLong Answer

Standards

CCSS.MATH.CONTENT.7.G.B.6CCSS.MATH.CONTENT.8.G.A.5

9 sections · Free to use · Printable

← More Math worksheets for Grade 9

Area of Irregular Figures

Name:

Date:

Score:

Read each question carefully and show all your work. Decompose irregular figures into basic geometric shapes (rectangles, triangles, circles) to find their areas. Round your answers to two decimal places where necessary.

1. Find the area of the figure shown below. All angles are right angles.

2. Calculate the area of the composite figure formed by a semicircle on top of a rectangle. The rectangle has a length of 12 cm and a width of 8 cm. The diameter of the semicircle is equal to the width of the rectangle.

3. An irregular shape can often be broken down into simpler geometric shapes such as , , and .

4. To find the area of an irregular figure, you must always subtract the areas of smaller shapes from a larger enclosing shape.

True

False

5. A garden is shaped like a rectangle with a triangular section removed from one corner. The rectangle is 15 meters long and 10 meters wide. The removed triangular section has a base of 4 meters and a height of 3 meters. What is the area of the garden?

6. Which of the following is NOT a common strategy for finding the area of an irregular figure?

Decomposing into basic shapes

Using the Pythagorean theorem directly on the area

Enclosing the figure in a larger shape and subtracting

Using a grid and counting squares

7. Describe in your own words the process of finding the area of an irregular figure. Provide an example.