Question 706116
m is number of miles driven.

E --- 
Cost is 30+0.20*m

H ---
Cost is 50+0*50, or 50+0.15(m-50) if m>50
EDIT: This means this two part function for H,
cost 50 if m<=50
cost 42.5+0.15m if m>50


You would make graphs of cost as a function of miles driven. Best if you do them both on the same graph paper or display instance.  Use a different color for each company.
EDIT:  Graphing these is much more easily done on real graph paper than on this algebra.com system.  The answer will be plainly visible.  Use miles m for the horizontal axis and use cost for the vertical axis.