A ship leaves port at 1:00 P.M. and sails in the direction S35°E at a rate of 24 mi/hr. Another ship leaves port at 1:30 P.M. and sails in the direction S20°W at a rate of 18 mi/hr. Approx. how far apart are the ships at 3:00pm I made a picture and I dont know if I need to add some to the side to correspond with the changing times
What is the question asking , i think you left that out in the directions.
Oh sorry. Approx. how far apart are the ships at 3:00pm
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I drew the south line just to aid us. So we want to know how far apart are the two vectors
first lets find the magnitude of each vector. Distance = rate * time
A ship leaves port at 1:00 P.M. and sails in the direction S35°E at a rate of 24 mi/hr. Another ship leaves port at 1:30 P.M. and sails in the direction S20°W at a rate of 18 mi/hr. Approx. how far apart are the ships at 3:00pm the first vector distance = 24 mi/hr * 2 hr = 48 mi second vector distance = 18 mi/hr * 1.5 hr = 27 mi
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now we can use law of cosines for that triangle
Law of cosines : a^2 + b^2 - 2*a*b*cos(C) = c^2 27^2 + 48^2 - 2*27*48*cos(20 + 35 degrees) = x^2
then take the square root of the both sides x = √ [27^2 + 48^2 - 2*27*48*cos(55 degrees)]
(24)(2) For the first vector, It wouldn't be something different because we started at 1:30 and we're going to 3?
That would be why perl only put "1.5 hr"
I get that for the second vector yes but the first one is at a different time
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the first vector (boat) travels from 1 pm to 3 pm, so 2 hours. the second vector (boat) travels from 1:30 pm to 3 pm, so 1.5 hours
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