Advanced Math practice question

Answer: 1

Case x − 4 = 2x + 1 gives x = −5, but then the right side is −9, which cannot equal an absolute value. Case 4 − x = 2x + 1 gives x = 1, and |1 − 4| = 3 = 2(1) + 1. So there is exactly one solution.

Common wrong answers

If you answered 0

x = 1 does satisfy the equation.

If you answered 2

2 counts x = −5, which fails the check because 2x + 1 is negative there.

If you answered -5

The question asks how many solutions, and −5 is not one of them anyway.

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