How do you multiply #(x y - 3) ( x y + 3)#?
1 Answer
Jul 11, 2017
Explanation:
We can apply the F.O.I.L method.
If you are not already familiar, F.O.I.L stands for First, Outside, inside, Last
We begin by multiplying the first terms in each parenthesis.
Next we multiply the outside terms:
Then the Inside terms:
And finally the last terms:
We then add all of them up to get the following expression:
We can simplify this further as the two middle terms cancel and we are left with this.