Equation of a Line Completing System with 3x - 2y = 8

[JHPB99]

Q: Write an equation of a line that forms a system with the equation 3x - 2y = 8 that has infinitely solutions.
A: 3x - 2y = 8.
I believe this to be correct because it makes an identical line to one of her correct answers (6x - 4y = 16) and nowhere did it specify that it had to be new. Could you tell me my mistake?

 

[HOI]

Did you really think that your teacher intended you to just copy what she had written? On a technical level repeating the same equation does NOT give a "system".