To factor the polynomial x² + 9x – 20, we need to find two numbers that multiply to give the constant term (-20) and add up to the coefficient of the x term (9).
The two numbers that satisfy these conditions are 10 and -2. This is because:
- 10 * (-2) = -20
- 10 + (-2) = 9
We can now rewrite the polynomial using these numbers:
x² + 9x – 20 = (x + 10)(x – 2)
So, the factored form of the polynomial x² + 9x – 20 is:
(x + 10)(x – 2)