Answer:
y=2x+1
Explanation:
Well, let's start with the graph given by the question. (Picture 1 below)
1) We can pick two points, (1,1) and (-1,-3), also for the slope we can see it's a positive one so m >0
2)

So now
y=mx+b
y=2x+b
Plugging in those values (1,1) and (-1,-3)
1=2(1)+b
b=-1
So y=2x-1, instead of 3y=2x+4