SAT Math Multiple Choice Question 379: Answer and Explanation
4. If p and q represent the zeros of a quadratic function and p + q = -3, which of the following could be the factored form of f(x)?
- A. f(x) = (x - 3)(x + 3)
- B. f(x) = (x - 4)(x + 1)
- C. f(x) = (x - 1)(x + 4)
- D. f(x) = (x - 6)(x + 3)
Correct Answer: C
Category: Passport to Advanced Math / Quadratics
Strategic Advice: When a quadratic function is written in factored form, you can find its zeros by setting each factor equal to 0 and solving for the variable. Knowing this will save valuable time on Test Day.
Getting to the Answer: Each of the answer choices is written in factored form, so mentally solve each one by asking yourself what number would make each factor equal to 0. Then find the sum of the results:
Choice A: 3 + (-3) ≠ -3. Eliminate.
Choice B: 4 + (-1) ≠ -3. Eliminate.
Choice C: 1 + (-4) = -3, so (C) is correct.
Choice D: 6 + (-3) ≠ -3. Eliminate.