Use the four-step process to find the slope of the tangent line to the graph of the given function at any point. (Simplify your answers completely.)

f(x) = 4 5x

Step 1:

f(x + h)

=

Step 2:

f(x + h) f(x)

=

Step 3:

f(x + h) f(x)

h

=

Step 4:

f'(x) =limh0

f(x + h) f(x)

h

=