1) 2y + 2j +3xy + 3xj =
(2y+2j)+(3xy+3xj)=
2(y+j)+3x(y+j)=
(2+3x)(y+j)
2) 5x4y + 3x2y -9xy -15xy2
5x4y -15xy2 + 3x3y -9y=
5xy (x3 -3y) +3y (x3 -3y)=
(x3 -3y)(5xy +3y)
3) 20ac + 15bc +4ad + 3bd =
(20ac + 4ad) + (15bc + 3bd) =
4a(5c + d) + 3b(5c + d)=
(4a + 3b)(5c + d)
4) 18a3 + 12a2 - 15a - 10 = (
18a3 + 12a2) - (15a + 10) =
6a2(3a + 2) - 5(3a + 2)=
(6a2 - 5)(3a + 2)
