Problema Solution
A rectangle has perimeter 60 m. Express the area of the rectangle as a function of its width.
Answer provided by our tutors
let
l = the length
w = the width
P = 60 m the perimeter
2(l + w) = 60 divide both sides by 2
l + w = 30
l = 30 - w
A = l*w is the area of the rectangle
plug l = 30 - w in the last equation
A = (30 - w)*w
A = 30w - w^2