Question

Help.. (1 pt) A rectangular page is to contain 180 square inches of print. The top and bottom margins are each 0.6 inches wide , and the margins on each side is 1.25 inches wide. What should the dimensions be if the least amount of material is to be used ?

(Leave your answers to 3 decimal places.)

Length of top(bottom) : inches
Length of side : inches

Answer 1

Assume the length of the paper is L and width W.

Area = LW (the area of the material used).
We want to minimize A.

You can find the dimensions of the printable area of the paper:
The length will decrease by the top and bottom margins: (L - .6 - .6) = (L - 1.2)
The width will decrease by the left and right margins: (W - 1.25 - 1.25) = (W - 2.5)

(L - 1.2)((W - 2.5) = 180.
Solve for L in terms of W. Substitute in the area formula and minimize by finding derivative and equation to zero.

Answer 2

will try this..