Answer: Direct variation - y = kx Inverse variation - y = k/x
Step-by-step explanation: Direct variation is used when a function is directly proportionate by a constant variable. Inverse variation is used when a function is inversely proportionate by a constant variable. Direct variation can be used to calculate salaries, time, or distance relating to a constant variable that is graphed as a straight line. Inverse variation can be used to calculate populations relating to a constant variable that is graphed as a curve.
