m²-m=m(m-1)
6+2a=2(a+3)
3m²-12=3(m²-4)=3(m+2)(m-2)
2m²-2=2(m²-1)=2(m+1)(m-1)
a³+2a²b=a²(a+2b)
5a-20=a(a-4)
3x³+9x²=3x²(x+3)
x²-3x=x(x-3)
2x²-4xy=2x(x-2y)
2x-2y=2(x-y)