1. 1.5 Using Formulas in Geometry

2. Definitions:
Perimeter: is the sum of the side lengths of a plane figure.
Area: is the number of nonoverlapping square units of a given size that exactly cover the plane figure

3. Formulas:

4. Examples:
Find the perimeter and area of each figure.

5. Example:
Find the perimeter and area of a square with a side length of 3.5 inches.
The Queens Quilt block includes 12 blue triangles. The base and height of each triangle are about 4 inches. Find the approximate amount of fabric used to make the 12 triangles.

6. Example:
Find the amount of fabric used to make four rectangles. Each rectangle has a length of 6.5 inches and a width of 2.5 inches.

7. Definitions:
Diameter- a segment of a circle that passes through the center of the circle and whose endpoints are on the circle.
Radius- a segment of a circle whose endpoints are the center of the circle and a point on the circle.
Circumference- The distance around the circle (perimeter)

8. Formulas:

9. Examples:
Find the circumference and area of a circle with a radius of 8 centimeters.
Find the circumference and area of a circle with a radius of 14 meters.