Algebra practice question

Answer: -2

For the set to be x ≥ 0, dividing by a must flip the sign, so a < 0, and then x − 2 ≥ 4/a, so 2 + 4/a = 0 → a = −2. Check: −2(x − 2) ≤ 4 → x − 2 ≥ −2 → x ≥ 0.

Common wrong answers

If you answered 2

2 gives x − 2 ≤ 2, so x ≤ 4, the wrong direction.

If you answered 4

4 gives x ≤ 3.

If you answered -1

−1 gives x ≥ −2.

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