We are given that "x" and "y" vary inversely. This means that the variables follow the next relationship:
Where "k" is a constant to be determined. To determine "k" we will use the given values:
Now, we plug in the values:
Now, we solve for "k" by multiplying both sides by 3:
Therefore, the value of "k" is 18. Now, we substitute in the relationship:
And thus we get the equation.