Direct Variation

In this section, we learn about Direct Variation and Direct Variation as a Power. In a direct variation problem, we say that y varies directly with (as) x if there is a constant value k such that: y = kx. The value k is known as the constant of variation or the constant of proportionality. In algebra 1, the variation problems are typically all the same. We are given an opening scenario that allows us to find k. We are then told to find y when x is a certain value. We begin by writing the generic formula: y = kx. We substitute the given values and solve for the constant of variation k. We then rewrite the equation with the known value of k and x. Once this is done, we can solve for the unknown y. When we see direct variation as a power, we use the same technique.