2m(a+b)+a+b=(a+b)(2m+1)
4x(m-n)-m-n=4x(m-n)-(m+n)=(m-n)(4x+1)
5x(a+b)-a-b=5x(a+b)-(a+b)=(a+b)(5x-1)
3m(x+y)-x-y==3m(x+y)-(x+y)=(x+y)(3m-1)
2m(a+b)+a+b=(a+b)(2m+1)
4x(m-n)-m-n=4x(m-n)-(m+n)=(m-n)(4x+1)
5x(a+b)-a-b=5x(a+b)-(a+b)=(a+b)(5x-1)
3m(x+y)-x-y==3m(x+y)-(x+y)=(x+y)(3m-1)