equilateral triangleEquilateralTriangle2001-10-06 17:57:142007-06-19 11:31:26DefinitionTriangle\usepackage{amssymb}
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An \emph{equilateral triangle} is one for which all 3 sides are congruent.
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The following statements hold in Euclidean geometry for an equilateral triangle.
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It is a regular polygon.
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The bisector of any angle coincides with the height, the median and the perpendicular bisector of the \PMlinkescapetext{opposite side}.
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If $r$ is the length of the side, then the height is equal to $\displaystyle \frac{r\sqrt{3}}{2}$.
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If $r$ is the length of the side, then the area is equal to $\displaystyle \frac{r^2\sqrt{3}}{4}$.
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