Chapter 4 Quadratic Functions and Factoring - 4.3 Solve x(squared) + bx + c = 0 - 4.3 Exercises - Skill Practice - Page 256: 52

-3, 15

Since the coefficient of the squared term is one, we know that the expression must factor to: $$ (x\pm a)(x\pm b)$$ Here, we see that a and b must multiply to get $-45$ and add to get $-12$. Thus, we find that the solution is: $$(x-15)(x+3)$$ Thus, setting each factor equal to zero, we find that the solutions are: $$-3, 15$$