Question

Completely factor the polynomial:

x2 + 9x + 20

Answer 1

Look for two numbers that multiply to +20 and sum to +9.
1 * 20 = 20
2 * 10
4 * 5
-1 * -20
-2 * -10
-4 * -5

Are all pairs of whole numbers that multiply to twenty, and only one sums to nine. 4 and 5. So, x² + 9x + 20 factors into (x + 4)(x + 5) (that's just the format). Multiply it out to check.

Answer 2

thanks for the help :)