1) x^2y+x+xy^2+y = x(y+1) + 1(y+1) = (x+1)(y+1)
2) 9a^2b-3a^2+3b^2-b = 3a^2(3b-1) + (3b-1) = (3a^2+1)(3b-1)
3) 8a^2-2ab-4ac+bc = 2a(4a-b) - c(4a-b) = (2a-c)(4a-b)
1) x^2y+x+xy^2+y = x(y+1) + 1(y+1) = (x+1)(y+1)
2) 9a^2b-3a^2+3b^2-b = 3a^2(3b-1) + (3b-1) = (3a^2+1)(3b-1)
3) 8a^2-2ab-4ac+bc = 2a(4a-b) - c(4a-b) = (2a-c)(4a-b)