SOLUTION: The variables x and y vary inversely. When x is 10 and y is 7. If x is 5, then y is ___ ? I do not understand how to set this up?

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Question 142245: The variables x and y vary inversely. When x is 10 and y is 7.
If x is 5, then y is ___ ?


I do not understand how to set this up?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
Use the model for inverse variation.
The model for direct variation is:
y+=+k%2Fx
Substitute 10 for x and 7 for y:
7+=+k%2F10
7%2A10+=+k…..
k=70…….

The inverse variation equation that relates x+and y is:
y+=+70%2Fx.........substitute x for 5
y+=+%2870%2F5%29
y+=+14+
If x is 5, then y is 14 .