# Precalculus Examples

, ,

Step 1

When three variable quantities have a constant ratio, their relationship is called a direct variation. It is said that one variable varies directly as the other two vary. The formula for direct variation is , where is the constant of variation.

Step 2

Solve the equation for , the constant of variation.

Step 3

Replace the variables , , and with the actual values.

Step 4

Step 4.1

Factor out of .

Step 4.2

Cancel the common factors.

Step 4.2.1

Factor out of .

Step 4.2.2

Cancel the common factor.

Step 4.2.3

Rewrite the expression.

Step 5

Raise to the power of .

Step 6

Write the equation of variation such that , replacing with the .