Question

A rectangle poster covers an area of 380.16 square inches of a display board. The width of the poster is 12 inches less than its length. Find the width of the poster.

Answer 1

Let the width = x -12
the length = x
we have this area equation: x(x-12)=380.16
=>x^2-12x-380.16=0
=>(5x-132)(5x+72)=0
=>x= 132/5 and x= -72/5 (no)

=>The width of the poster is: 132/5 -12 =72/5 inches