Question

Find the length of the side CD in the Pentagon ABCDE

Answer 1

As shown at the graph :

the coordinates of point C is (8,2)

The coordinates of point D is (4, -2)

The distance CD is d can be found from the following formula:

`\begin{gathered} d=\sqrt[]{(x2-x1)^2+(y2-y1)^2} \\ d=\sqrt[]{(8-4)^2+(2-(-2)^2}=\sqrt[]{4^2+4^2}=\sqrt[]{16+16}=\sqrt[]{32}=4\sqrt[]{2} \end{gathered}`

the distance CD = 4√2 = 5.657 (to the nearest 3 decimals)