By Ron Woldoff

The SAT Math exam contains questions where you’ll need to know how to factor down a quadratic equation. The following practice questions ask you to do that, and then to plug in your solution to solve a given expression.

Practice questions

  1. What is the value of
    if ab = 1/3 and a + b = 6?
  2. What is the value of p2 + q2 if p2q2 = 7 and p4q4 = 28?
    A. 2
    B. 3
    C. 4
    D. 5

Answers and explanations

  1. The correct answer is 25.
    Remember that a2 b2 = (a + b)(ab). Plug in the values of a + b and ab to solve for a2b2:
    Now plug 2 in for a2b2:
  2. The correct answer is Choice (C).
    Start by factoring p4q4:
    Now plug in the values that the question gives you: