# Pythagorean theorem

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# Pythagorean theorem

### Learn

### Practice

### Learn

### Practice

### About this unit

The Pythagorean theorem describes a special relationship between the sides of a right triangle. Even the ancients knew of this relationship. In this topic, we’ll figure out how to use the Pythagorean theorem and prove why it works.

Identify your areas for growth in these lessons:

Test your understanding of **Pythagorean theorem** with these 9 questions.