Rectangle

A rectangle is a quadrilateral with four right angles. All rectangles are parallelograms.

 

The Properties of a Rectangle:

1. Opposite sides are parallel, i.e., \(\begin{align*}AB \parallel CD\end{align*}\) and \(\begin{align*}BC \parallel DA\end{align*}\).

2. Opposite sides are congruent, i.e., \(\begin{align*}AB = CD\end{align*}\) and \(\begin{align*}BC = DA\end{align*}\).

3. All the four angles are congruent and measure \(\begin{align*}90^\circ\end{align*}\), i.e., \(\begin{align*}\angle ABC\end{align*}\)\(\begin{align*}=\end{align*}\)\(\begin{align*}\angle{BCD}\end{align*}\)\(\begin{align*}=\end{align*}\)\(\begin{align*}\angle{CDA}\end{align*}\)\(\begin{align*}=\end{align*}\)\(\begin{align*}\angle{DAB}\end{align*}\)\(\begin{align*}= 90^\circ\end{align*}\).

4. Diagonals are congruent, i.e., \(\begin{align*}AC = BD\end{align*}\).

5. Diagonals bisect each other, i.e., \(\begin{align*}BO = OD\end{align*}\) and \(\begin{align*}AO = OC\end{align*}\).