AlgebraVery hardValue of a constant for a given solution
Algebra practice question
In the equation 3(x − k) = 2x + 1, k is a constant. If x = 7 is the solution, what is the value of k?
- A. 2Correct
- B. 5
- C. −2
- D. 7
Answer: A. 2
Substitute x = 7: 3(7 − k) = 15, so 7 − k = 5 and k = 2.
Why the other answers are wrong
- B. 5
- 5 is 7 − k, not k.
- C. −2
- −2 has the wrong sign.
- D. 7
- 7 is x, not k.
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