Question

graph the function

f(x)=-4x

Answer 1

This is tough to type so you'll have to do the work:
First substitute a few values for the x, say -2, -1, 0, 1 and 2
You'll get 4 values for f(x) -4(-2)=8
-4(-1)=4
-4(0)=0
-4(1)=-4
-4(2)=-8
Next in a graph you plot those 5 points (-2,8), (-1,4), (0,0), (1,-4) and (2,-8)
then just draw a line through all those points and you're set.
If the line is a little short for your chart, just use a ruler and extend it as far as you like

Answer 2

good answer,
if you know about slopes yet you could also start at origin and count down 4 over 1