Algebra practice question

Answer: 5

Substitute x = 3: 15 − 4 = 6 + b, so 11 = 6 + b and b = 5.

Common wrong answers

If you answered 11

11 is the left side, 5(3) − 4, before subtracting the 2x term.

If you answered 17

17 adds 6 to 11 instead of subtracting it.

If you answered -5

−5 has the wrong sign: 11 − 6 = 5.

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