# Interactive video lesson plan for: Area circumradius formula proof | AIME | Math for fun and glory | Khan Academy

#### Activity overview:

Proof of the formula relating the area of a triangle to its circumradius. Created by Sal Khan.

Watch the next lesson: https://www.khanacademy.org/math/math-for-fun-and-glory/aime/2003-aime/v/2003-aime-ii-problem-6?utm_source=YT&utm_medium=Desc&utm_campaign=mathforfunandglory

Missed the previous lesson? https://www.khanacademy.org/math/math-for-fun-and-glory/aime/2003-aime/v/2003-aime-ii-problem-5-minor-correction?utm_source=YT&utm_medium=Desc&utm_campaign=mathforfunandglory

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