Math Pythagorean theorem Cathetus and hypotenuse

# Cathetus and hypotenuse

Prerequisite for the Pythagorean theorem is a right triangle. Every right triangle always has a $90^\circ$ angle. If the triangle does not have a right angle, none of these phrases applies.

If the requirement is fulfilled, you have to determine the catheti and the hypotenuse first:

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### Remember

• The hypotenuse is the opposite side to the right angle. It is also the longest side in the triangle.

• Catheti are the other two sides that are not opposite to the right angle.