How do you find the area of a regular Pentagon with an apothem of 5 and each of its sides are 10ft long?

Regular pentagon can be divided into 5 congruent triangles.

The area of a triangle = 1/2 * (base*height)

In our case base pf the triangle is the side of the pentagon, and the height of the triangle is an apotheme of the pentagon.

So, A (triangle) = (1/2) * 10*5 = 25 ft².

We have 5 triangles in pentagon,

so A (pentagon) = 5*25=125 ft².