help me with this fast and explain it for brainiest :)

So i think it would be 1/2 (OR .5), or possibly 2 depending on what its asking.
Every number in X can be multiplied by 2 to receive y, or the numbers in y.
The linear equation would be x*2=y, making the linear function 2, UNLESS you want to take Y and DIVIDE it by 2, making it 1/2, linear equasion would be y*.5=x, or y/.5=2 OR y*1/2=x.
Hope this helps, I'm so sorry if its wrong, I'm not too good at linear functions, I'm pretty sure its 1/2.