Algebra practice question

Answer: 3

Expand: 2x − 2 + 3x + 6 = 19, so 5x + 4 = 19. Then 5x = 15 and x = 3.

Common wrong answers

If you answered 2

2 comes from 5x + 9 = 19, adding the constants as 3 + 6 instead of −2 + 6.

If you answered 4.6

4.6 comes from 5x − 4 = 19, with the signs of the constants mishandled; −2 + 6 = +4.

If you answered 3.8

3.8 is 19/5, ignoring the constant 4.

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