#related rates

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autumn drift
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A plane flying with a constant speed of 240 km/h passes over a ground radar station at an altitude of 2 km and climbs at an angle of 30°. At what rate is the distance from the plane to the radar station increasing a minute later? (Round your answer to the nearest whole number.)
km/h

devout lance
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so, lets start with that

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what can we use to determine the distance?

autumn drift
devout lance
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yea

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and then, what two values are the sides of the right triangle

autumn drift
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240 & 2?

devout lance
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well, the airplanes position changes as a function of time, no?

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so, can you get the coordinates of it for t minutes or hours, depending on what you like, after it is at 240,2?

autumn drift
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honestly u lost me

i am so utterly confused

devout lance
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how did you learn related rates btw

autumn drift
devout lance
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i learned it the wrong way after someone tried to teach me the correct way :P

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but its more effective for me

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just confusing to others

autumn drift
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@devout lance ??? sorry im so lost

devout lance
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okay, so uhhh

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what would be the coordinates of the plane after 1 hour

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and keep in mind the calculation you do to get that

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then try getting 2 hours, half hour, etc., see if you notice a pattern

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and that might help you find a general form for the coordinates of the plane

autumn drift
autumn drift
devout lance
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okay lets draw a diagram to help us out here

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how familiar are you with coordinates

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like if i did coordinate geometry here would that confuse you

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so the plane is 2 km above

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n stuff

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now if the angle there is 30, how can we find the general equation of the line

devout lance
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okay lets swap to the other type of related rate solving

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well its basically the same thing buy

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but*

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we draw a right angle from the base to the airplane, right now, it has a side of 0 and 2...

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so now we want to find at what rate these sides are increasing

autumn drift
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@devout lance whered u get 0 from? im utterly confused respectfully

devout lance
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okay yea thats fair

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so we can make a right triangle

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one leg is the horizontal distance from the plane to the base

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the other is the vertical distance

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right?

autumn drift
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@devout lance nvm i finally got the answer but ty

tardy lavaBOT
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@autumn drift has given 1 rep to @devout lance

autumn drift
# devout lance yay! gj

thanks but i still have no idea what im doing

the website had a video with a problem similar so i just did what that person did

tardy lavaBOT
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@autumn drift has given 1 rep to @devout lance

devout lance
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you can check khan academy for some nice course stuff