SOLUTION: antonio paddles 1 mile upstream and 1 mile back in the total time of 1 hour. The speed of the river is 2 miles per hour. Find the speed of Antonios paddleboat in still water?

Algebra ->  Length-and-distance -> SOLUTION: antonio paddles 1 mile upstream and 1 mile back in the total time of 1 hour. The speed of the river is 2 miles per hour. Find the speed of Antonios paddleboat in still water?      Log On


   

Question 923062: antonio paddles 1 mile upstream and 1 mile back in the total time of 1 hour. The speed of the river is 2 miles per hour. Find the speed of Antonios paddleboat in still water?
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
antonio paddles 1 mile upstream and 1 mile back in the total time of 1 hour. The speed of the river is 2 miles per hour. Find the speed of Antonios paddleboat in still water?
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let x=speed of paddleboat in still water
x+2=speed of paddleboat downstream
x-2=speed of paddleboat upstream
travel time=distance/speed
1%2F%28x-2%29%2B1%2F%28x%2B2%29=1
lCd:(x+2)(x-2)
x+2+x-2=(x+2)(x-2)
2x=x^2-4
x^2-2x-4=0
solve for x using quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1, b=-2, c=-4
x+=+%282+%2B-+sqrt%28+4-4%2A1%2A-4+%29%29%2F%282%2A1%29+
x+=+%282+%2B-+2sqrt%28+5+%29%29%2F%282%29+
x=1±√5
x≈3.23
speed of Antonios paddleboat in still water? 3.23 mph