Answer:
Area of a regular decagon with a perimeter of 60 ft. = 277 squared ft
Step-by-step explanation:
Decagon has 10 sides So 60/10 = 6 (each side = 6ft )
The sum of the interior angles of a decagon is 1 440 degrees.
There are 10 equal isosceles triangles of base angles 72 degrees in a decagon
Each isosceles triangle can subdivided into 2 right-angled triangles with height h and base length = (6/2) = 3 cm and base angle 72 degrees.
Height of right-angled triangle h = 3 tan 72 ft.
Area of 1 right-angled triangle = (1/2)(3)(3 tan 72) = 13.85 squared ft
Area of decagon = 20 right-angled triangles = 277 squared ft
