Question 123300
Pick two values for x.  You can pick any values you like, but I usually pick something that makes the arithmetic easy.  0 and 7 would work well here.


Evaluate the function at each of the values you chose giving you a value for the function at each of the x values.


Now you have two ordered pairs (x,y) that you can plot on your graph.  If you used the 0 and the 7, then f(0) = 0 - 7 = -7, and f(7) = 7 - 7 = 0, so your two points would be (0, -7) and (7, 0).


Once you have plotted your two points, construct a line through them.  Done.


{{{graph(400,400,-2,10,-10,2,x-7)}}}