1. (y+b) (x+b) 2. (a+b) (b+a) 3. (y+a) (y*2+y+a) 4. (a+a) (a*2+y+a)

1. xy + by + bx + b^2
2. ab + a^2 + b^2 + ab = a^2 + 2ab+ b^2
3. y^3 + y^2 + 2 ay + ay^2 + a^2
4. 2a^3 + 2 ay + 2 a^2

urutin yaa, berdasarkan pangkat hehee