1. Area of Composite Figures
Objective: Find the area of composite figures.

2. Composite Figures:

3. Formulas of Areas: Area of a Rectangle: Area = Length × Width
Area of a Triangle: Area = Base × Height 2
Area of a Trapezoid: Area = (base 1 + base 2) × height

4. More Formulas: Area of a Semi-Circle: Area = π x r2 2
Area of a Circle: Area= π x r2
Area of a Semi-Circle: Area = π x r2 2

5. Example 1: Find the area of the composite figure shown below:

6. Example 1: In order to find the area of the composite figure:
Separate the composite figure into a:
Semi-circle and a
Rectangle.

7. Solution: Total Area = 140 + 76.93 = 216.93 mm2 2 A = 3.14 × 72
Area 1: Semi-circle or Half circle
Area 2: Rectangle:
Semicircle: A= π × r2 2
A = 3.14 × 72
A = 3.14 × 49
A = mm2 = 76.93
Rectangle: A= L × W
A= 10 × 14
A= 140mm2
Total Area = = mm2

8. Example 2: Find the area of the composite figure:
How many figures do you see? _____

9. Example 2: Find the area of the composite figure:
Separate the composite figure into a:
Triangle
Rectangle and a
Semi-circle

10. Solution: Total Area = 60 + 12 + 14.13 = 86.13 in2 Area 1: Triangle
Area 2: Rectangle
Area 3: Semi-circle
Triangle: A = b × h 2
A= 4 × 6
A = 24
A = 12in2
Semi circle: A = π × r2 2
A = × 32 ÷ 2
A = × 9 ÷ 2
A = ÷ 2
A = in 2
Rectangle: A = L × W
A = 10 × 6
A = 60 in2
Total Area = = in2

11. Your Example: Find the area of this figure
Your Example: Find the area of this figure. ( Separate the figure in shapes, find the area, then add them up.)
Separate the figure into 3 shapes: 2 rectangles and
1 semi circle.

12. Homework: Find the area of the following composite figures: