Algebra practice question

Answer: 8

The same line means one equation is a multiple of the other. The second equation's left side, 4x − 2y, is exactly 2 times 2x − y, so its right side must be 2 times 4: k = 8.

Common wrong answers

If you answered 2

2 is the multiplier between the equations, not the value of k. Apply it to the 4: 2 × 4 = 8.

If you answered 4

With k = 4, the second equation is 4x − 2y = 4, which simplifies to 2x − y = 2 — a different, parallel line.

If you answered 16

16 is 4 × 4. The left side was multiplied by 2, so the right side is multiplied by 2, giving 8.

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