Which Operations? (Part 2)

This Instructional Activity is a part of the Lesson 3, Unit 1, Grade 7. In the previous activity, students saw that subtracting the same value from all side lengths of a polygon did not produce a (smaller) scaled copy. This activity makes the case that adding the same value to all lengths also does not produce a (larger) scaled copy, reinforcing the idea that scaling involves multiplication. This activity gives students a chance to draw a scaled copy without a grid and to use paper as a measuring tool.