Answer:
f(x)=-3x+2
Explanation:
The first one is a quadtratic function because it is in quadtratic form.
The second one is also not linear because it looks like a squiggly line. Sorry I forgot what they are called but I know it is not linear.
That leaves the last one is is linear and should be going down because there is a negative in front of the coefficient. It also has so exponent to prove why it is linear even further.
Hope this helps!