Slide 1

I can use proportions to find missing measures in similar figures 7.4 Similar Figures

Slide 2

Vocabulary corresponding sides corresponding angles similar

Slide 3

Matching sides of two or more polygons are called corresponding sides, and matching angles are called corresponding angles.

Slide 4

Two figures are similar if the measures of the corresponding angles are equal. the ratios of the lengths of the corresponding sides t are proportional. Similar Figures Similar figures have the same shape but not necessarily the same size.

Slide 5

Similar Figures (Not exactly the same, but pretty close!)

Slide 6

Finding Missing Measures in Similar Figures The two triangles are similar. Find the missing length y and the measure of D.

Slide 7

This reduction is similar to a picture that Katie painted. The height of the actual painting is 54 centimeters. What is the width of the actual painting? The width of the actual painting is 81 cm.

Slide 8

This reduction is similar to a picture that Marty designed. The height of the actual picture is 39 inches. What is the width of the actual picture? 4 in. 3 in. The width of the actual painting is 52 inches.

Slide 9

1. These two triangles are similar. Identify the missing length x. A. 3 cm B. 4 cm C. 5 cm D. 6 cm Lesson Quiz for Student Response Systems

Slide 10

2. These two triangles are similar. Identify the measure R. A. 30 B. 50 C. 80 D. 90 Lesson Quiz for Student Response Systems

Slide 11

3. These two triangles are similar. Identify the missing length y. A. 27 in. B. 21 in. C. 9 in. D. 8 in. Lesson Quiz for Student Response Systems

Slide 12

A carpenter is making a rectangular table top of dimensions 9 ft by 12 ft. However, he is going to increase its size proportionally. If the width is to be 15 ft, what will the length be? A. 24 ft B. 20 ft C. 18 ft D. 12 ft

Slide 13

I can use proportions and similar figures to find unknown measurements 7.5 Indirect Measurement

Slide 14

Use the similar triangles to find the height of the tree. The tree is 21 feet tall.

Slide 15

A rocket casts a shadow that is 91.5 feet long. A 4-foot model rocket casts a shadow that is 3 feet long. How tall is the rocket? The rocket is 122 feet tall.

Slide 16

On a sunny afternoon, a goalpost casts a 75 ft shadow. A 6.5 ft football player next to the goal post has a shadow 19.5 ft long. How tall is the goalpost? 25 feet

Slide 17

On a sunny afternoon, a tree casts a 120-foot shadow. A 6-foot man beside the tree has a shadow 36 feet long. How tall is the tree? A. 20 ft B. 30 ft C. 36 ft D. 60 ft