Proportional Relationships and Equations

What's the Direct Variation or Direct Proportionality Formula?

Ever heard of two things being directly proportional? Well, a good example is speed and distance. The bigger your speed, the farther you'll go over a given time period. So as one variable goes up, the other goes up too, and that's the idea of direct proportionality. But you can express direct proportionality using equations, and that's an important thing to do in algebra. See how to do that in the tutorial!
How Do You Solve a Proportion Using the Multiplication Property of Equality?

Trying to find a missing value in a ratio to create proportional ratios? You could use the multiplication property of equality! In this tutorial, see how to use this property to find a missing value in a ratio. Take a look!