posted by Lucy .
Find the slope of the line passing through the points at (a, a+3) and (4a, a-5).
2) Together, two printers can print 7500 lines if the first printer prints for 2 minutes and the second prints for 1 minute. If the first printer prints for 1 minute and the second prints for 2 minutes, they can print 9000 lines together. Find the number of lines per minute that each printer prints.