Pythagorean Theorem
Section: GeometryBank code: GEO-PYTGRE frequency: Very HighPro
1. Core Idea
In a right triangle with legs a, b and hypotenuse c:
a^2 + b^2 = c^2
The hypotenuse is always opposite the right angle and is always the longest side. Getting that identification right is more than half the battle.
The theorem also works in reverse: if a^2 + b^2 = c^2 for the three sides, the triangle is right-angled.
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