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

So the boxes cut out are each X.

The little cut out squares are each x by x or x^2.

Therefore the area of the new shape is 300-4x^2 and the new width is going to be 20-2x