When modeling real world situations, we often use what's called inverse or indirect variation to describe a relation between two variables. Indirect variation is a relation in which the absolute value of one variable gets smaller while the other gets larger. Indirect variation and direct variation are important concepts to understand when learning equations and interpreting graphs.
Inverse variation or indirect variation, two different ways of saying the exact same thing and with this particular concept we're just going to jump right in it and take a look at it so y varies inversely as x. So what this actually mean is whenever that something varies it's always going to be by itself so this is y is equal to and inversely basically means instead of being on the same level, They're on opposite levels so we're going to divide for this okay y varies inversely as x we divide and with any variation problem we always need a constant. Why this is called inversely is what happens is the bigger x gets, the smaller y gets and the smaller x gets the bigger y gets so there's an indirect inverse variation, they're opposite, whereas direct one gets bigger the other one gets bigger and inversely one gets bigger the other gets smaller, there's an opposite.