Question

The volume of Olivia's rectangular lunchbox is 240 cubic inches. The lunchbox has a height of 3 inches, and its length is 2 inches more than its width. How wide is Olivia's lunchbox?

Answer 1

Volumn = Height*Width*Length
Width*(Width+2)=Volumn/Height=240/3=80
Width^2 +2Width-80=0
(Width-8)(Width+10)=0
Width>0 -> Width+10>0
-> Width-8=0 -> Width=8 inches