(x+2)²-(y+2)²
(x+2-(y+2))(x+2+(ý+2))
(x+2-y-2)(x+2+y+2)
(x-u) (x+4+y)
(2x+3)²-(3-x)(x+3)
4x²+12x+9-(3-x)(3+x)
4x²+12x+9-(9-x²)
4x²+12x+9-9+x²
5x²+12x
(x+2)²-(y+2)²
(x+2-(y+2))(x+2+(ý+2))
(x+2-y-2)(x+2+y+2)
(x-u) (x+4+y)
(2x+3)²-(3-x)(x+3)
4x²+12x+9-(3-x)(3+x)
4x²+12x+9-(9-x²)
4x²+12x+9-9+x²
5x²+12x