Answer: 110 square cm
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Step-by-step explanation:
All sides of a regular polygon are the same length. So the bottom side is also 8 cm.
Draw lines from the center to each vertex of the pentagon. Five triangles form. Each triangle has a base of 8 and a height of 5.5 (since all five triangles are congruent)
area of one triangle = 0.5*base*height = 0.5*8*5.5 = 22
area of five triangles = 5*(area of one triangle) = 5*22 = 110