Rational Functions: Direct and Inverse Variation

Finding Inverse Variation Equations

Finding inverse variation equations is the same as finding direct variation equations, but the general equation is different.

For example, suppose y varies inversely as x, and y = 4 when x = 7, find the inverse variation equation.

The first step is to find k. Use the general equation y equals k divided by x and the information given in the problem to solve for the constant of variation.

y equals k divided by x, 4 equals k divided by 7, k equals 28

This means that the inverse variation equation is y equals 28 divided by x.