SAT Math Multiple Choice Question 499: Answer and Explanation
If (a, b) is a solution to the system of equations above, which of the following could be the value of b?
- A. -3
- B. -2
- C. 1
- D. 2
Correct Answer: A
Category: Passport to Advanced Math / Quadratics
Strategic Advice: The solution to a system of equations is the point(s) where their graphs intersect. You can solve the system algebraically by setting the equations equal to each other, or you can solve it graphically using your calculator. Use whichever method gets you to the answer more quickly.
Getting to the Answer: Both equations are given in calculator-friendly format (y = …), so graphing them is probably the more efficient approach. The graph looks like:
The solution point in the question is given as (a, b), so b represents the y-coordinate of the solution. The y-coordinates of the points of intersection are -3 and -1.25, so choice (A) is correct.