# Equilateral Triangles

I found that the area of an equilateral triangle is sqrt(3)xS^2/4 where S is the side length But if I put it in a square, shouldn't the area be s^2/2?  Note by Zoe Codrington
2 years, 9 months ago

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If you put it in a square, the top vertice won't touch the side of the square.

- 2 years, 9 months ago

Ok, thanks

- 2 years, 9 months ago

Did anyone else get this as their childhood interpretation of the A=bh/2 proof with equalateral triangles? I did.

- 2 years, 9 months ago

no, I better understood it with calculus. I am no geometer. I like to visualise it using functions and Cartesian graphs.

- 2 years, 8 months ago

It is impressive to do it with geometry; it requires a very visual brain.

- 2 years, 8 months ago

I know this is messy, but please?

- 2 years, 9 months ago - 2 years, 9 months ago

But is it possible to somehow prove without using Pythagoras Theorem or common sense? Edit:I just worked out the proof, but if you have ways to prove it other than the angles of an iscoceles triangle and possibly angles of an equaliteral triangle it would be interesting to hear.

- 2 years, 9 months ago