Answer:
Explanation:
Alright so let me try and explain this as best as I can:
So the graph isn't linear because the graph shows a parabola (a boomerang kind of shape that happens if you use an exponent somewhere in a y=mx+b formula if I remember correctly) and not a straight line. Linear graphs cannot curve, and this one does. Not sure why it it would be a function though. Assuming the answer chosen is correct, my best guess as to why it might be a function is because it continues to go in the same direction forever, there is a predictable amount of change between each point and you can follow a formula to find every point on the graph.
I really hope this helps a little!