rhomboidRhomboid2007-06-05 12:52:342007-06-06 14:40:47Definition\usepackage{amssymb}
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A \emph{rhomboid} is a parallelogram that is neither a rhombus nor a rectangle. The word rhomboid comes from the Greek word $\rho o \mu \beta o \varepsilon \iota \delta \acute\eta \varsigma$, which is transliterated as `rhomboeidis'. In \emph{The Elements}, Euclid has this definition:
\begin{quote}
``Of quadrilateral figures....a rhomboid (is) that which has its opposite sides and angles equal to each other but is neither \PMlinkname{equilateral}{Equilateral} nor \PMlinkname{right-angled}{RightAngle}.''
\end{quote}
Below is a picture of a rhomboid.
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The \PMlinkescapetext{formula} for the area of a rhomboid is the same as that for all parallelograms: If $b$ is the length of its \PMlinkescapetext{base} and $h$ is the length of its \PMlinkescapetext{height}, then $A=bh$.