In this lesson, we will learn:

- Identifying Types of Variations
- Translating Variation Statements Into Equations
- Solving Variation Problems
- Word Problems of Variations

- Joint variation is a direct variation, but with two or more variables. It has the equation $y=k \cdot x \cdot z$ where $k$ is the constant of variation and $k \neq 0$.
- A combined variation is formed when we combine any of the variations together (direct, inverse and joint). In most cases, we combine direct and inverse variations to form a combined variation. i.e. $y$ varies directly with $x$ and inversely with $z$ $(y = k \cdot \frac{x}{z})$
- Steps to solving a variation problem:
- Write the general variation formula of the problem.
- Find the constant of variation $k$.
- Rewrite the formula with the value of $k$.
- Solve the problem by inputting known information.