How to answer it
- Set the equation equal to zero.
- Factor if two numbers multiply to the constant and add to the middle coefficient.
- Set each factor to zero and check both answers.
Worked example
An original question in the SAT format, already answered.
SAT MathWorked example
x² − 5x + 6 = 0
What are the solutions of the equation?
- A−2 and −3
- B2 and 3
- C1 and 6
- D−1 and 6
Answer: B. −2 and −3 multiply to 6 and add to −5, so the equation factors as (x − 2)(x − 3) = 0. That gives x = 2 or x = 3.
The most common trap
Taking the signs from the factors. (x − 2) = 0 means x = 2, not −2.
Practice it
Hourly Prep’s daily sets mix nonlinear equations and systems with the rest of SAT Math, and send more of it your way when it’s a weak spot. See how the SAT prep plan works, or browse the other SAT skill guides.