First the equation needs to be set to "y" to find the total amount of miles traveled: y= Then you know he has already gone 3.5, this is a constant and can be added to the graph immediately y=3.5 Then you know every two hours he can cover 100 miles, which means 50 miles per hour or 50 per x, so add 50x to 3.5 to show that he will go 3.5 miles plus 50 miles for every hour he is traveling. y=3.5+50x