CPM Homework Help : GC Problem 9-9

Find the area of a regular decagon with perimeter $100$ units. Show all work.

Hint:

Find the length of each side, then find the central angle.

More Help:

Use the tangent ratio to find the height of the triangle, then find the area of the triangle.

Step:

$h=\frac{5}{\tan{18°}}$

Hint 2:

Use the area of the triangle to find the total area of the shape.