Answer: He has 7 books.
Step-by-step explanation:
9 - 2 = 7
100% of the original number
FOIL stands for first, outer, inner, and last.
So, you multiply the first terms together, the outer terms together, the inner terms together, and then the last terms together.
(b+3)(b-9)
b^2-9b+3b-27 Then simplify
b^2-6b-27