Answer:
x: length
y: wide
x = 3y and x*y =192
=> 3y^2 = 192
=> y = 8 => x =3x8 = 24
=> Perimeter = (x+y)*2 = (8+24)*2 = 64
The answer should be -2x^2+6x
The polynomial x3+8 is equal to (x+2)(x2-2x+4)
