Uploaded October 2010 | Updated September 2026, 3 weeks ago

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Around 60 C.E., Heron of Alexandria developed a formula for the area of a triangle in terms of its three side-lengths solely (thus giving no need to find the height of the triangle first). This result is often presented in the school curriculum without proof. Here is its proof!

It is worth noting that the formula was discovered by Chinese and Islamic scholars as well.