Easy!
Since the greatest multiple of 9 lesser than 79 is 72, you get a remainder of 7
8 7/9
For this you need to multiply 1,500 by 60 (because there are 60 seconds in a minute) and then multiply that by 2 (because there are 2 minutes), wich makes the answer 180,000 meters.
Does this help?
I think the answer is the slope is -2 and the y-intercept is 12