What is the formula for finding area of a pentagon?

Answer 1

[ONLY WORKS FOR REGULAR PENTAGONS] I don't the exact formula, BUT, from what I learned in Geometry last year, I remember that if you have the radius from the center perpendicular to a side [for height] and if you have the length of the side of the pentagon, you can use a simple 1/2 times base time height to get 1/5th of the area. Then you just take that and multiply it by 5 to get the area of the whole pentagon.

I know it looks complicated, but it's pretty simple:

I have a REGULAR pentagon that I chop into 5 triangles

I have the height = 2

I have the base [or the length of 1 side of the pentagon]= 4

1/2xbasexheight= 1/2x2x4= 4

So now you have the area of 1 triangle and multiply by 5

4x5= 20

your pentagon is 20 units squared.

I hope this helped.