Instructional Activity# Adding Up Areas

Lesson 7. Unit 8. Grade 8 Open Up Resources

Open Up Resources15 min(s)

This Instructional Activity is a part of the Lesson 7, Unit 8, Grade 8. The purpose of this activity is for students to work through an area-based algebraic proof of the Pythagorean Theorem. One of the figures used in this particular proof was first encountered by students at the start of the year during a unit on transformations and again in a recent lesson where they reasoned about finding the area of the triangles. While there are many proofs of the Pythagorean Theorem similar to the one in this activity, they often rely on (a+b)^2=a^2+2ab+b^2, which is material beyond the scope of grade 8.