Let x represent one side of equilateral triangle. Next, we know that the perimeter of the equilateral triangle= side+side+side,so P=x+x+x with the P=15x^3+33x^5 feet 15x^3+33x^5=3x Divided both side by 3 (15x^3+33x^5)/3=3x/3 x=5x^3+11x^5 x=x³(5+11x²) feet. As a result, the length of each side is x³(5+11x²) feet. Hope it help!