Question

What is the area of the regular pentagon

Answer 1

D) 172.05 cm²

Explanation:

Area of a pentagon with side s :

`A = (1)/(4) \sqrt{5(5+2√(5)) } \;s^2\\\\=(1)/(4) \sqrt{5(5+2√(5)) } \;(10)^2\\\\=(100)/(4) \sqrt{25+10√(5) } \\\\= 25\sqrt{25+10√(5) }\\\\=172.05`