Download presentation

1
**Congruence and Similarity**

2
Similar Two shapes are similar if their corresponding angles are equal and their corresponding sides are in proportion.

3
**Bottom Length 10 cm Top Length 3 cm**

4
Congruent Two shapes are congruent if all corresponding angles AND sides are equal. If two shapes are congruent, they are also similar.

5
Top Length 4 cm Bottom Length 5 cm

6
Perimeter To find the perimeter of any polygon, add up the length of all sides.

7
**Triangles Triangles have 3 angles that add up to 180 degrees.**

To find the area of a triangle, multiply ½ the base x the height.

8
**Rectangles Rectangles have 4 right angles that add up to 360 degrees.**

To find the area of a rectangle, multiply the length x the width.

9
Scale Factor The ratio of corresponding side lengths of two similar figures. All congruent shapes have a scale factor of 1:1.

10
**B A The scale factor from A to B is 5:2.**

Length = 10 cm Width = 5 cm The scale factor from A to B is 5:2. The ratio of areas from A to B is 25:4 Length = 4 cm Width = 2 cm B

11
Missing Side You can find the missing side length on one of two similar figures by using a proportion involving scale factor.

12
**B A Set up a proportion. Cross multiply and divide. 20 = 5 4 x**

A and B are similar. A Length = 20 cm Width = 5 cm Set up a proportion. Cross multiply and divide. = x So, x = 1 cm B Length = 4 cm Width = ? cm

13
Missing Angle You can find the measure of a missing angle on one of two similar triangles by subtracting from 180 degrees.

14
**If triangles xyz and def are similar, what is the measure of angle y?**

500 y z d Y = 60 degrees because = 120. 180 – 120 = 60. e f 700

Similar presentations

© 2024 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google