SOLUTION: If y is directly proportional to u and inversely proportional to the square of v, and y=7 when u=9 and v=6, what is y when u=4 and v=8?

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Question 943683: If y is directly proportional to u and inversely proportional to the square of v, and y=7 when u=9 and v=6, what is y when u=4 and v=8?
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The language for the first parts means y=k%28u%2Fv%29, and you can solve this for k, use the values for the variables given in the next part, and determine the value of k.

Answer by MathTherapy(10551) About Me  (Show Source):
You can put this solution on YOUR website!

If y is directly proportional to u and inversely proportional to the square of v, and y=7 when u=9 and v=6, what is y when u=4 and v=8?

y+=+ku%2Fv%5E2
7+=+k%289%29%2F6%5E2
7+=+9k%2F36
7+=+k%2F4
k = 7(4), or k = 28 ------ Cross-multiplying
y+=+ku%2Fv%5E2
y+=+28%284%29%2F8%5E2
y+=+112%2F64
highlight_green%28y+=+system%28%287%2F4%29_or%2C1.75%29%29