Question 350438
let width be: x-5
Let length be: x

x(x-5)=84
x^2-5x=84
x^2-5x-84=0

x=5+√25+336
x=5+19 or x=5-19
x=24/2 or x=-14/2
x=12 or x= -7(NO can't be negative)

L=12