Find an equation of variation in which y varies inversely as x and the following is true:

y=31, when x=4

Originally, I mixed up the equations of inverse and direct variation, and got 31=m(4)
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b

Obviously, I got it wrong, but I've gone ahead and redid the problem, and I'd just like somebody to check it for me:

y=k/x
31=4K
(divide both sides by 4)

y=7.75

x y = k

To find the equation of variation in which y varies inversely as x, we start with the general equation:

y = k/x

where k is the constant of variation.

To find the value of k, we can substitute the given values of y and x into the equation. We are given that when x=4, y=31. Plugging these values into the equation, we get:

31 = k/4

To solve for k, we can multiply both sides of the equation by 4:

31 * 4 = k

k = 124

Now that we have the value of k, we can substitute it back into the equation to get the final equation of variation:

y = 124/x

Therefore, the correct equation of variation in which y varies inversely as x is y = 124/x.