Lesson 9

An image of a book shown on a website is 1.5 inches wide and 3 inches tall on a computer monitor. The actual book is 9 inches wide.

1. What scale is being used for the image?
2. How tall is the actual book?

The flag of Colombia is a rectangle that is 6 ft long with three horizontal strips.

• The top stripe is 2 ft tall and is yellow.
• The middle stripe is 1 ft tall and is blue.
• The bottom stripe is also 1 ft tall and is red.

1. Create a scale drawing of the Colombian flag with a scale of 1 cm to 2 ft.

2. Create a scale drawing of the Colombian flag with a scale of 2 cm to 1 ft.

These triangles are scaled copies of each other.

For each pair of triangles listed, the area of the second triangle is how many times larger than the area of the first?

1. Triangle G and Triangle F

2. Triangle G and Triangle B

3. Triangle B and Triangle F

4. Triangle F and Triangle H

5. Triangle G and Triangle H

6. Triangle H and Triangle B

Here is an unlabeled rectangle, followed by other quadrilaterals that are labeled. 

1. Select all quadrilaterals that are scaled copies of the unlabeled rectangle. Explain how you know.
2. On graph paper, draw a different scaled version of the original rectangle.