Question 767651
Width = x
Length = 3 + x
Removal of 3cm^2 from each corner.
Width = x - 6
Length = 3 + x - 6 = x - 3
Volume = length*width*height
120 = (x - 3)*(x - 6)*(3)
120 = 3x^2 - 27x + 54
Combine
3x^2 - 27x + 54 - 120 = 0
3x^2 - 27x - 66 = 0
3(x^2 - 9x - 22) = 0
3(x - 11)(x + 2) = 0
x + 2 = 0
x = -2 (no answer x<0)
x - 11 = 0
x = 11
Width = 5cm
Length = 8cm
Height = 3cm
Hope this helps.
:-)