Lesson 8

Finding Unknown Side Lengths

Lesson Narrative

The purpose of this lesson is to use the Pythagorean Theorem to find unknown side lengths of a right triangle.

Learning Goals

Teacher Facing

  • Calculate unknown side lengths of a right triangle by using the Pythagorean Theorem, and explain (orally) the solution method.
  • Label the “legs” and “hypotenuse” on a diagram of a right triangle.

Student Facing

Let’s find missing side lengths of right triangles.

Learning Targets

Student Facing

  • If I know the lengths of two sides, I can find the length of the third side in a right triangle.
  • When I have a right triangle, I can identify which side is the hypotenuse and which sides are the legs.

CCSS Standards


Building Towards

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