1. 6.2 USE PROPORTIONS TO SOLVE GEOMETRIC PROBLEMS Goal:You will use proportions to solve geometry problems.

2. d c b d c + d d

3. Use properties of proportions Example 1: In the diagram,. Write four true proportions. 1. Since then _________________________ 2. Since then _________________________ 3. Since, then _________________________ 4. Since, then _________________________ 12 9 18 x 12 9 12 18 9 x = = = =

4. Use proportions with geometric figures In the diagram, Find and On Your Own 2: In the example above. Find AC. AC

5. A scale drawing is a drawing that is the same shape as the object it represents. The scale is a ratio that describes how the dimensions in the drawing are related to the actual dimensions of the object.

6. Example 3: The blueprint shows a scale drawing of an “old” cell phone. The length of the antenna on the blueprint is 5 centimeters. The actual length of the antenna is 2 centimeters. What is the scale of the blueprint?

7. Example 4: The scale of the map at the right is 1 inch: 26 miles. Find the actual distance from Pocahontas to Algona

8. HOMEWORK p. 367 3-14, 16, 17, 22-29