Similarity and Congruency (Enlargement)

Everything you need for a lesson observation is here. This is a very constructive lesson that you will not be disappointed with. This is an active inspire flipchart with worksheets.

Starter - Basic Scale Factor for enlargement of squares, rectangles and triangles with answers provided.

Discussion 1 - The starter links for discussing what similarity is from the shapes they enlarged. Students are shown two shapes and are asked if they are similar and why. This being that the lengths have been multiplied by the same number (SF) meaning they are similar. Identifying similarity, congruency and none is discussed here.

Activity 1 - Pair activity identifying similarity, congruency and none + answers

Discussion 2 - Identifying Scale factor from two shapes given they are similar. Working out SF and finding missing lengths. Challenging similar triangle shapes included for discussion.

Activity 2 - Differentiated worksheet task covering all of the above.
- Calculating SF
- Finding missing lengths using SF
- Finding missing lengths for complex triangle similar shapes
Answers included

Plenary - Provides a link to the real world or to test them against the GCSE question at the start to demonstrate good progress