16Hit1600
AlgebraEasy–MediumTesting a value in an inequality

Algebra practice question

Which of the following values of x satisfies 4x − 7 ≥ 9?

  1. A. 4Correct
  2. B. 3
  3. C. 2
  4. D. 0

Answer: A. 4

Solve: 4x ≥ 16, so x ≥ 4. The value 4 itself works because the inequality includes equality: 4(4) − 7 = 9, and 9 ≥ 9 is true.

Why the other answers are wrong

B. 3
4(3) − 7 = 5, and 5 ≥ 9 is false.
C. 2
4(2) − 7 = 1, well below 9.
D. 0
4(0) − 7 = −7, which is not at least 9.

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