Algebra practice question

Answer: -6

The lines must be parallel: the first has slope 3 and the second has slope −k/2, so −k/2 = 3 and k = −6. The constants 4 and 7 are not proportional, so the lines are distinct.

Common wrong answers

If you answered 3

3 copies the first coefficient.

If you answered 6

6 has the sign wrong.

If you answered -3

−3 forgets the factor of 2.

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