Algebra practice question

Answer: 3

From the second, x = 4 − 2y. Substitute: 5(4 − 2y) − 3y = 7, so 20 − 13y = 7 and y = 1. Then x = 2, and x + y = 3.

Common wrong answers

If you answered 1

1 is y alone.

If you answered 2

2 is x alone.

If you answered 4

4 is the constant in the second equation, not x + y.

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