Question

actor a2 + 4ab – 45b2 on your paper. Which one of these is a factor of the trinomial

(a + 3b)
(a – 9b)
(a – 5b)
none of the above

Answer 1

\[a ^{2}+4ab-45b ^{2}=a ^{2}+5ab-9ab-45b ^{2}\]
=\[a(a+5b)-9b(a+5b)=(a-9b)(a+5b)\]
Now, can u see the factors?