Equilateral Triangle
Triangle whose three sides are congruent.
Property
A triangle is an equilateral triangle if its three angles are congruent and they all measure 60°.Formula
The formula to calculate the area A of an equilateral triangle is: [latex]A=\frac{c^{2}}{4}\sqrt{3}[/latex] The formula to calculate the radius r of the circle circumscribed about an equilateral triangle is: [latex]r=\frac{c}{3}\sqrt{3}[/latex] The formula to calculate the radius r of the circle inscribed in an equilateral triangle is: [latex]r=\frac{c}{6}\sqrt{3}[/latex]Example
This is an equilateral triangle: