Quadratic Word Problems Using Factoring, Quadratic Formula

Page 44 #2 Suppose a schooner leaves a port at 12 noon travelling at 10 km per hour due East. Five hours later, a ferry leaves the same port travelling at 2okm/h due north. At what time of day will the two boats be 100 km apart?

Page 44#2 Let x= time in hours after noon If the schooner is travelling East left at noon and the schooner going north did not leave until 5 hours later, then the first schooner is already gone 5 times 10km/h or 50km before the second schooner leaves.

Page 44, #2 Since East and North are perpendicular we have a diagram like this:

Page 44 #2

Since x=number of hours after noon the x cannot equal -5 so x=3. Thus they are 100 km apart at 3pm.