Algebra practice question

Answer: 4

For infinitely many solutions the equations must be multiples: 12/6 = 6/3 = 2, so a/2 = 2 and a = 4.

Common wrong answers

If you answered 1

1 divides the wrong way.

If you answered 2

2 would make the x-coefficients equal but not the whole equation a multiple.

If you answered 6

6 copies the y-coefficient.

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