A regular hexagon has a perimeter of p (in length units) and an area of A (in square units). If $A = 9,$ then find the side length of the hexagon.
Area of hexagon = 6 * 1/2 * (side)^2 *sqrt (3) / 2
So
9 = 6 * (1/2) *(side)^2 * sqrt (3) /2
9 = (3/2) sqrt (3) * (side)^2
9 / [ (3/2) sqrt (3)] = side^2
6/sqrt 3 = side^2
2sqrt 3 = side ^2
sqrt [ 2sqrt 3] = side ≈ 1.8612
+102 
