Direct Variation

What is direct variation?

Direct variation occurs when one variable depends directly on another variable. As one increases, the other must increase at the same rate. A common example is how much you earn per week is directly proportional to the hours you worked. The steps below show you how to solve a direct variation problem in Prelim Standard Math:

1. Write an equation relating the two variables together (k is the constant. If y is directly proportional to x then the equation is y=kx)
2. Solve the equation for k by substituting the x and y values
3. Write the equation with the solution for k and solve the problem by substituting to find the final answer desired

How to solve direct variation questions

The videos below explain the concept of direct variation and solve real-life problems using the equation.

Part 1

Part 2

Part 3

Part 4

Part 5