A book designer decided that the pages of a book should have 1-in. margins at the top and bottom and 1 2 in. margins on the sides. She further stipulated that each page should have an area of 50 in. 2. Find a function in the variable x, giving the area of the printed region

A = 54.8 - (1200/x) - 2x

Step-by-step explanation:

Given x the wide and y the height, we have

x*y = 50

⇒ y = 50/x

The area of the printed region is A = w*h

where

Wide: w = (x-2*1.2) = x-2.4

Height: h = (y-2*1) = y-2

then

A = (x-2.4) (y-2) = xy - 2.4y - 2x + 4.8 = 50 - 24 * (50/x) - 2x + 4.8

⇒ A = 54.8 - (1200/x) - 2x