Question 1003708
let length be x
width = (x-3)

Area = L*w

x(x-3) = 100

x^2-3x =100
x^2-3x=100

x^2-3x +(9/4) = 100+9/4

(x-(3/2))^2 = 409/4

{{{x-(3/2)}}} = +/- {{{sqrt(409)/2}}}

x= 3/2 + {{{sqrt(409)/2}}}  OR x = (3/2) - {{{sqrt(409)/2}}}

ignore negative value

x= 11.61 => ;length

y = 8.611 => width

CHECK

11.61*8.61 = 99.96 sq ft