## Algebra and Trigonometry 10th Edition

y = $\frac{k}{x^{2}}$
If variables vary directly then y = x, so as one increases then the other increases. If variables vary inversely then y = $\frac{1}{x}$, as one increases the other decreases. In this example, y = $\frac{k}{x^{2}}$ where k is a constant. This is the form since the variables are inversely related, and x needs to be squared.