Algebra practice question

Answer: -1 or −1

From the second, x = 6 + 2y. Substitute: 2(6 + 2y) + 3y = 5, so 12 + 7y = 5 and y = −1. (Then x = 4.)

Common wrong answers

If you answered 1

1 has the wrong sign; 7y = 5 − 12 = −7.

If you answered 4

4 is x, not y.

If you answered -7

−7 is 7y, not y.

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