Question

Find the product mentally.

(ab + 3)(ab - 3)

A.a^2b^2 + 9

B.a^2b^2 - 6ab - 9

C.a^2b^2 - 9
____
Im guessing its "A"? Am I correct?

Answer 1

C

Answer 2

(A-B)(A+B) = A^2 - B^2

Answer 3

^

Answer 4

I keep geting the + And - Mixed up

Answer 5

yeah what sourwing put it right

Answer 6

if its in that form it will always be minus