Explain the x axis and y axis plane

How do you answer this question? (step by step)

Noel is hoping to make a profit (in $) on the school play and has determined the function describing the profit to be f(t) = 8t – 2654, where t is the number of tickets sold. what does the number 8 tell you?

Car a and car b were in a race .the driver of car b claimed that his car was twice as fast as car a