Heron's formulaHeronsFormula2001-10-06 17:27:342004-11-27 14:02:59TheoremGeometryAreaTriangle\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{graphicx}
\usepackage{xypic}The area of a triangle with side lengths $a,b,c$ is
$$\triangle=\sqrt{s(s-a)(s-b)(s-c)}$$
where $s=\frac{a+b+c}{2}$ (the semiperimeter).
\begin{center}
\includegraphics{triangulo}
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