SOLUTION: My math question: if y varies directly with x, and if y=26 when x=4, find y when x is 7. if y varies inversely with x and y=4 when x=1, find y when x is 28. that's all the pro

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Question 376745: My math question:
if y varies directly with x, and if y=26 when x=4, find y when x is 7.
if y varies inversely with x and y=4 when x=1, find y when x is 28.
that's all the problem says. it's not specific on what to do. i have no idea how to start the problem :'( is there some type of formula to use?
thank you for the help!
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Varies Directly



is called the constant of variation and has to be determined using the initial conditions given.

If when , substitute:



Then solve for



Then put back into the original equation.



Then for



Varies Inversely

Works exactly the same way except that you start with:



John

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