Write an algebraic expression that represents the surface area of a box whose width is 7y, the height is 5y and the length is 8y + 5. SA = 2(L)(W) + 2(L)(H) + 2(W)(H), where L is the length, W is the width, and H is the height of the box. Find the dimensions of the box if the surface area is 2718 m2.