Polynomials and measurements

Question

A box is 15 x 20 inches. In the box there are cut out squares of the same size from each corner. Mark the side of the cut-out square by x. Write an expression that represents the width of the box.

Answer 1

let x = the side of each square corner cut out

the box is (15-2x) by (20-2x) = width by length

width= 15-2x inches

where 0 < x < 7.5 inches

width = w

and 0 < w < 15 inches

w = 15 - 2x