17) solve the problem. 17) three tanks have a total capacity of 409 gallons. if two tanks are the same size and the other tank is half of their size, how many gallons does the smallest tank hold? 2.5x 409 . z. s2.5 + 18) solve the problem. the total length of 3 pipes is 34 inches. the middle-sized pipe is 6 inches longer than the smallest. the largest is twice as long as the smallest. how long is the large-sized pipe? 18) 2 8 hi = l+lx 19) solve the problem. 19 n=3(x- 7)+ ty3 for x - 6, y 9, t = 7