Answer:
(a + 8)(a + 1)
Step-by-step explanation:
We know that the first term is squared, so we can put it out like this:
a * a
The third term has to be separated so that the sum of the two factors is the coefficient of the second term, 9.
8 = 4 * 2 (does 4 +/- 2 = 9? nope, we can't use that)
8 = 8 * 1 (does 8+/- 1 = 9? yes, when 8 + 1)
So the factor is a + 8 and a + 1.
Put this together and (a+8)(a+1)
