How do you use the zero factor theorem to solve #x^2 + 2x - 15#?
You use the zero factor theorem to find the results of a quadratic after you have factored it.
For example (From the website above):
By the definition of the Zero Factor Theorem, we know that one or both of those factors has to equal zero.
Therefore to find the solution to the problem we solve each factor for
Solution 1 will be found by solving
Solution 2 will be found by solving