1) b(a+c)+2a+3c = b(a+c) + 3(a+c) = (b+3)(a+c)2) c(a-b)+3a-3b = c(a-b) - 3(b-a) = c(a-b) - 3(-1)(a-b) = (c-3)(a-b)3) x-y+a(x-y) = (x-y)(a+1)4) y(b-x)+x-b = (y-x)(b-1).
1) b(a+c)+2a+3c = b(a+c) + 3(a+c) = (b+3)(a+c)
2) c(a-b)+3a-3b = c(a-b) - 3(b-a) = c(a-b) - 3(-1)(a-b) = (c-3)(a-b)
3) x-y+a(x-y) = (x-y)(a+1)
4) y(b-x)+x-b = (y-x)(b-1).