Well,. you could say bees in hive + bees in garden = bees in total.
When x=-5, y=(1/5)*(-5)-1=-2, so the first order pair is (-5,-2)
when y=-1, -1=(1/5)x-1, (1/5)x=0, x=0, so the second ordered pair is (0, -1)
1800 gal converts to 7200 quarts, and divide that by 60 you get 120 quarts of water per second.