Find the areas of composite figures.

1. Composite Figures
The student is able to (I can):
• Find the area of composite figures

2. composite
figure
A shape made up of simple shapes such as
triangles, rectangles, trapezoids, and
circles.
To find the area of the composite figure,
divide the shape into the simple shapes,
find the areas of each, and add (or
subtract) them.

3. Examples Find the area of each shape. Round to the
nearest tenth if necessary.
1.
38
20
70
40
3238
(20)(38) = 760

4. Examples Find the area of each shape. Round to the
nearest tenth if necessary.
1.
38
20
70
40
760
3238
− =2 2
40 32 24
24
( )( ) =
1
32 24 384
2
384
Area = 760 + 384 = 1144
(20)(38) = 760

5. Examples 2.
17" 42"
8"
Area = Triangle — ½ Circle
= =
1
Triangle (17)(42) 357 sq. in.
2
= π = π211 Circle (4 ) 8 sq. in.2 2
= − π ≈A 357 8 331.9 sq. in.

6. Examples 3. Find the area of the shaded portion to
the nearest tenth.
6 ft.
( )= π = π2 2
Circle 3 9 ft
( )( )= = 21
Square 6 6 18 ft
2
= π − ≈ 2
Area 9 18 10.3 ft