Question

A motorboat travels 9 miles downstream (with the current) in 30 minutes. The return trip upstream (against

takes 90 minutes.
Which system of equations can be used to find x, the speed of the boat in miles per hour, and y, the speed
current in miles per hour? Recall the formula d = rt.
9 = 0.5(x - y)
9 = 1.5(x + y)
9 = 1.5(x -y)
9 = 0.5(x + y)
0.5 = 9(x -y)
1.5 = 9(x + y)
1.5 = 9(x -y)
0.5 = 9(x + y)

Answer 1

The answer to the problem is the second one

Answer 2

Answer is B as marked

Explanation:

x+y is the speed of the boat + speed of the current.. both made the trip with 30 mins

that would be 0.5(x+y) = 9

return trip is speed of boat - speed of current

so it's 1.5(x-y)=9