12a²b-8ab²=2ab(a-4b)25(x-y)-6mn(x-y)=(x-y)(5-6mn)3a(x-3)+2b(3-x)=(x-3)(a-2b45(y-x)³+10(x-y)²=(y-x)²(5y-5x+2)
12a²b-8ab²=a×2ab-4b×2ab=2ab(a-4b)25(x-y)-6mn(x-y)=(x-y)(5-6mn)3a(x-3)+2b(3-x)=a(x-3)-2b(x-3)=(x-3)(a-2b)45(y-x)³+10(x-y)²=5(y-x)³+10(y-x)²=5(y-x)²×(y-x)+5(y-x)²×2=5(y-x)²(y-x+2)