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anonymous
 5 years ago
i need to know the answer to this
suppose x varies directly as r, and x varies inversely as t. find t when r equals 10 and x equals 5, if t equals 20 when x equals 4 and r equals 2
anonymous
 5 years ago
i need to know the answer to this suppose x varies directly as r, and x varies inversely as t. find t when r equals 10 and x equals 5, if t equals 20 when x equals 4 and r equals 2

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amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0So we are given this: x = r/t

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0or really: x = kr/t where k is any constant, but lets make that constant a "1" for simplicities sake :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0t = r/x then: t = 10/5

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0its not rate over time. i need to find t!

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0ack!! r = xt lol i forgot how to multiply :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0i see i forgot how to read the question as well..... let me start over :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0Find t when r=10 and x= 5, if t=20 when x= 4 and r=2 whats this mean?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0its a variation function

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0are you looking for the Constant? or what?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.04 = k(2/20) 40 = k x = 40r/t

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0just finding the answer for t

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0alright, hold on a minute and I will help, I just need to refresh my memory.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0First you need to set up a proportion. Since x varies directly as r and inversely as t, it will look like this:\[x_{1}t _{1} / r _{1} = x _{2}r _{2} / r _{2}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You plug in your values, which would make \[(4)(20) / 2 = 5(t)/10\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you then solve the proportion by cross multiplying, like so: \[(80)(10) = 2(5t)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0or, 800 = 10t ; solving the equation leaves you with t = 80.

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.05 i think it was :) which makes it 80 right?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ah true, thanks for pointing that out, I always get my signs messed up

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0i was just wondering if i did it right.... :)
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