PSAT Math Multiple-Choice Question 550: Answer and Explanation

Question: 550

Which ordered pair (x, y) satisfies the pair of equations below?

3x + y = -3

x - 2y = -8

• A. (2, 4)
• B. (-2, 3)
• C. (-3, 2)
• D. (1, -4)

Correct Answer: B

Explanation:

(B) You can use substitution to solve, although elimination could also work.

3x + y = -3

x - 2y = -8

Rearrange the second equation to be in terms of y:

x - 2y = -8

x = 2y - 8

Substitute into the first equation and solve for y:

3x + y = -3

3(2y - 8) + y = -3

6y - 24 + y = -3

7y - 24 = -3

7y = 21

y = 3

Then plug in 3 for y into the first equation to solve for x:

3x + y = -3

3x + 3 = -3

3x = -6

x = -2