A rectangular piece of cardboard measures 17cm by 14cm.strips of equal width are cut off one side and one end. The area of the remaining piece is 108cm. Find the width of the strips removed.
(17-w)(14-w) = 108
238 - 31 w + w^2 = 108
w^2 - 31 w +130 = 0
w = 5 or 26 see https://www.mathsisfun.com/quadratic-equation-solver.html
26 is hard to cut off 17 or 14
so use 5