Algebra practice question

Answer: 10

At x = 2 on the first line: 6 + 2y = 12, so y = 3. The point (2, 3) is on the second line too: 2k − 12 = 8, so 2k = 20 and k = 10.

Common wrong answers

If you answered 3

3 is the y-coordinate of the intersection, not k.

If you answered 4

4 is k with y = 0 (2k = 8), but the point's y-coordinate is 3, not 0.

If you answered -2

−2 comes from 2k + 12 = 8, adding 4y instead of subtracting it.

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