Thursday

March 5, 2015

March 5, 2015

Posted by **Taina** on Friday, June 24, 2011 at 12:18pm.

- math -
**Reiny**, Friday, June 24, 2011 at 1:21pmDon't know what the "five-step process" is, but here is how I would solve it ....

let her speed in still water be x km/h

time to go upstream = 10/(x-5)

time to go downstream = 10/(x+5)

solving : 10/(x-5) + 10/(x+5) = 3

10x + 50 + 10x - 50 = 3x^2 - 75

3x^2 - 20x - 75 = 0

x = (20 ± √1300)/6

= 9.34 km/h or a negative, which we reject

her still-water speed is 9.34 km/h

**Answer this Question**

**Related Questions**

algebra - rowing. Abby rows 10 km upstream and 10 km back in a total time of 3 ...

intermediate algebra - Rowing. Abby rows 10km. upstream and 10km. back in a ...

applications involving quadratic - Abby rows 10 km upstream and 10 km back in a ...

7th Grade Math - Toni rows a boat 4.5km/h upstream and then turns around and ...

math - a man rows downstream for one hour and 40 minutes on a river flowing at 2...

algebra - Abby Tanenbaum paddled her canoe 10 miles upstream, adn then paddled ...

Math - Toni rows a boat 4.5 km/h upstream and then turns around and rows 5.5 km/...

math - donna took 3hours to row 18 km upstream. her return trip took 1 hour less...

Math - Walking at 4km/h, Bruce can make the roundtrip between his campsite and ...

Algebra 2 - Walking at 4km/h, Bruce can make the roundtrip between his campsite ...