Question

Set up trigonometric ratios for three separate regular pentagons with different givens:

Answer 1

From the taingle

Using trigonometric ratio it follow

The length ofa sde of the pentagon is

`\begin{gathered} 2*5tan36 \\ = \end{gathered}`

Therefore the perimeter of the pentagon is \:

`\begin{gathered} 5*2*5*\tan36 \\ =50tan36 \\ =36.32 \end{gathered}`

Therefore the area of the perimter is

`\begin{gathered} A=(1)/(2)*36.32*5 \\ A=90.8 \end{gathered}`