# Equilateral triangle calculator

Please enter one property of the equilateral triangle

Use symbols: a, h, T, p, r, R

If you know the length of one side of an equilateral triangle (a), you can use that information to find the perimeter (p) of the triangle: p = 3a

You can also use the side length to find the area of the triangle using the formula:

Area = (√3/4) * a

^{2}

You can also use the side length to find the height (h) or the inradius (r) of the triangle:

h = (a√3)/2

r = a/(2√3)

If you know the area of an equilateral triangle, you can use that information to find the length of one side (a) using this formula:

Area = (√3/4) * a

^{2}

You can also use the area to find the height (h) or inradius (r) of the triangle:

h = (2 * √(3 * area))/a

r = √((2 * area)/√3)

If you know the height (h) of an equilateral triangle, you can use that information to find the length of one side (a) using this formula:

a = (2 * h)/√3

Calculate an equilateral triangle by:

### An equilateral triangle in word problems in mathematics:

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The funnel has the shape of an equilateral cone. Calculate the surface wetted with water if we poured into the funnel 7.1 liters of water.

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#### Look also at our friend's collection of math problems and questions:

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