Step 1: Multiply a and c
a = 1
c = 20
a * c = 20
Step 2: Find factors of +20 that add up to +9
Factors of 20 = 1, 2, 4, 5, 10, 20
The two factors that add up to 9 are 4 and 5.
Step 3: Factor
(x + 4)(x + 5) = 0
Answer: (x + 4)(x + 5) = 0
Hope this helps!