Algebra practice question

Answer: 9

Substitute y = x/3: 2x + 3(x/3) = 2x + x = 3x = 27, so x = 9. (Then y = 3.)

Common wrong answers

If you answered 3

3 is y, not x.

If you answered 13.5

13.5 is 27/2, ignoring the 3y term, which equals x.

If you answered 5.4

5.4 is 27/5, treating 3y as 3x instead of x.

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