how do you factor (a+b)^2-a-b?

Question

(a+b)^2-a-b. I can't figure out how to factor it. The answer is supposed to be (a+b)(a+b-1). I'm really sure that it's really simple and I'mjust missing the answer by making it too complicated.

Answer 1

(a+b)^2 -a-b =
(a+b)^2 - (a+b)

factor the (a+b) term out to get

(a+b)*(a+b-1)

Answer 2

(a+b)^2-a-b
=(a+b)*(a+b)-a-b
=(a+b)*(a+b)-(a+b)
=(a+b)*((a+b)-(1))
=(a+b)*(a+b-1)

Answer 3

(a+b)^2 = a^2+2ab+b^2
so
(a+b)^2-a-b=a^2+b^2+2ab-a-b