Answer:
Linear
Explanation:
This is linear because using the data you have provided we can work out that the equation is y= -5x+27
y= mx+ c (c is the gradient)
This equation shows that the line is straight (also shown in the picture) and therefore must make it a linear graph.
For the graph to be non linear, the graph would be curved but this would mean the equation would have to be a quadratic - which it isn't.
Hope this helps!