if you know that two sides are 5 inches long and the other two sides are 4 inches long then add 5+5+4+4 which equals 18 so then subtract 27 from 18 and you get 9 which is the length of the last side. 9 inches. I hope this helps
Let the boat speed in still water be b. Let the current speed be c. The speed going upstream is 20/4 = 5 mph. The speed going downstream is 32/4 = 8 mph. b - c = 5 ........(1) b + c = 8 .......(2) Adding equations (1) and (2) we get: 2b = 13 b = 13/2 = 6.5 Plugging in the value for b into equation (1) we find c = 1.5. The boat speed in still water is 6.5 mph and the current speed is 1.5 mph.
