How Far Does the Student Swim Across the River?

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The student swims across a 40 m wide river and ends up 30 m downstream, prompting questions about calculating the distance moved. The discussion involves using trigonometric functions to determine the hypotenuse of the triangle formed by the river's width and the downstream distance. The swimming speed of 1.2 m/s is acknowledged as relevant for understanding the scenario but not directly needed for calculating the distance across the river. Participants clarify their approach and confirm their understanding of the problem. Ultimately, the student successfully resolves the question.
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1. In still water, a student can swim at 1.2 m/s. She swims perpendicularly across a 40 m wide river, landing 30 m downstream. In crossing the river, what distance does the student move?



2. d=df-di, cosine, sine, tangent



3. Again, i tried drawing out a picture. I made 40m the x axis, and 30m the y axis. Am i trying to solve for the hypoteneuse? Also, what am i suppossed to do with the 1.2m/s. is it just there to try and mess me up? or is it important for the question?
 
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dance_sg said:
Am i trying to solve for the hypoteneuse?
That's what I would do.

dance_sg said:
Also, what am i suppossed to do with the 1.2m/s.
Data sufficiency.
 
sorry. i will remember that for next time.

and ok! thank you. i figured it out
 
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