2. A rectangle whose perimeter is 80 m has an area of 384 m^2. Find the dimensions of the rectangle. Solve it as a polynomial.

1 answer

If the width is w, we have

w(40-w) = 384
w^2 - 40w + 384 = 0
since 384 = 4*96 or 8*48 or 12*32 or 16*24 - aha!
(w-16)(w-24) = 0

Now you can easily figure the dimensions. Note that width is usually considered to be less than the length.