SOLUTION: let y vary directly as x. If y-10 when x=4, what is x when y =7?

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Question 33339: let y vary directly as x. If y-10 when x=4, what is x when y =7?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
y varies directly as x means y=kx
Need to find "k".
10=k(4)
k=(5/2)
EQUATION:
y=(5/2)x
Find "x" when y=7.
7=(5/2)x
x=14/5
Cheers,
Stan H.