a rectangle has a length 4m less than twice its width. when 4m are added to the width, the resulting figure is a square with an area of 144m square. Find the dimension of the original rectangle.

let width = x

length = 2x-4

when width = 4+x

area = (2x-4)(x+4) = 144

=> 2x^2 +4x - 16 = 144

=> x^2 + 2x - 80 =0

=>(x+10)(x-8)=0

=> x = 8

width = 8 m

length = 12 m