Direct Proportionality
Given two variables x and y, y is directly proportional to x (x and y vary directly, or x and y are in direct variation) if there is a non-zero constant k such that
The relation is often denoted, using the ∝ symbol, as
and the constant ratio
is called the proportionality constant or constant of proportionality.
Read more about this topic: Proportionality (mathematics)
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