Question

Y varies inversely with x. y=4 when x=-3. What is the constant of variation?

Answer 1

Explanation

We are to find the constant of variation

To get the constant of variation, we will first have to get the formula that connects x and y

So, we have that

Y varies inversely with x.

Thus

$y\propto\frac{1}{x}$

By introducing the constant of variation and the inequality sign, we will have

$\begin{gathered} y=k\times\frac{1}{x} \\ The\text{ formula connecting them is} \\ y=\frac{k}{x} \end{gathered}$

Next, we are told that

y=4 when x=-3

so

$4=\frac{k}{-3}$

Cross multiplying

$k=4\times-3=-12$

Therefore, the value of k is -12

The constant of variation is -12