If f (3) = 9 and f ´(3) = 4, find the tangent line to the graph of f when x = 3.
y = 4x - 3
y = 4x + 21
y = 9x - 23
y = 9x + 31
f '(3) = 4 says that the slope is 4 when x = 3
f)3) = 9 means that you are dealing with the point (3,9)
So they have given you the slope of the line and a point on it.
I am sure you can take it from there.