The regular pentagon has five sides equal. If this divided into five triangles and we can solve the area of the triangle, then we can solve for the area of the regular pentagon.
The solution is shown below:
Area triangle = 1/2*base*height
base = 8.7 inches
height = 6 inches
Area triangle = 1/2*8.7 *6 = 26.10 in²
We can solve now for the area of the regular polygon such as shown below:
Area regular pentagon = 5 * 26.10
Area regular pentagon = 130.5 in²
The answer is 130.5 inches².