8.2: Similar Figures

1) Lesson Objectives:

At the end of the lesson, you should be able to:

1. Identify similar figures have the same shape but different size.

2. State the properties of similar figures

• All corresponding angles are equal

• All corresponding sides have equal ratio

Big Idea:

• Invariance is a property of a mathematical object which remains unchanged when the object undergoes some form of transformation. In geometry, the area of a figure, the angles within it, and the ratio of the sides remain unchanged when the figure is translated, reflected or rotated.

Success Criteria:

• I know 2 figures are similar when 1) all corresponding angles are equal OR 2) All corresponding sides have equal ratio.

• I am able to find unknown angles or sides using the properties of similar figures.

Always look through all examples in textbook before lesson.