Prove theorems about triangles. Theorems include: a line parallel to one side of a triangle divides the other two proportionally, and conversely; the Pythagorean Theorem proved using triangle similarity.

Popular Tutorials in Prove theorems about triangles. Theorems include: a line parallel to one side of a triangle divides the other two proportionally, and conversely; the Pythagorean Theorem proved using triangle similarity.

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  How Do You Use the Triangle Proportionality Theorem to Find Missing Lengths in a Diagram?

  This tutorial shows you how the Triangle Proportionality Theorem can be used to find a missing length in a diagram. Take a look!