AlgebraMediumParameter for a point on a line
Algebra practice question
The point (k, k + 3) lies on the graph of 5x − 2y = 9. What is the value of k?
Answer: 5
Substitute: 5k − 2(k + 3) = 9, so 3k − 6 = 9 and k = 5.
Common wrong answers
- If you answered 1
- Remember to distribute the −2 over both k and 3: −2(k + 3) = −2k − 6.
- If you answered 3
- 3 is the coefficient 5 − 2; solve 3k − 6 = 9 to get k = 5.
- If you answered 15
- 15 is 3k; divide by 3 for k = 5.
More Algebra questions
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