Question

2(a-b)+a(a-b)= 2(x-y)-a(x-y)= (m+1)-m(m+1)= 7(x+y)-a(x+y)= 2(a-b)+c(b-a)= 4(m+n)+(m+n)= 2a(b-3)-5c(3-b)=

Answer 1

$2(a-b)+a(a-b)=(a-b)(2+a)=2a+a^2-2b+b^2\\2(x-y)-a(x-y)=(x-y)(2-a)=2x-ax-2y+ay\\(m+1)-m(m+1)=(m+1)(1-m)=m-m^2+1-m=-m^2+1\\7(x+y)-a(x+y)=(x+y)(7-a)=7x-ax+7y-ay\\2(a-b)+c(b-a)=(a-b)(2-c)=2a-ac-2b+cb\\4(m+n)+(m+n)=5(m+n)=5m+5n\\2a(b-3)-5c(3-b)=(b-3)(2a+5c)=2ab+5bc-6a-15c$