Direct and Inverse Variation

Direct variation is a relationship between two variables where one variable is a constant multiple of the other. It can be expressed as y = kx, where k is a non-zero constant.

Inverse variation is a relationship between two variables where the product of the two variables is a constant. It can be expressed as xy = k, where k is a non-zero constant.

The formula for direct variation is y = kx, where k is the constant of variation.

The formula for inverse variation is xy = k, or y = k/x.

y = 25.

y = 4.

The constant of variation (k) represents the ratio of y to x, indicating how much y changes for a unit change in x.

The constant of variation (k) represents the product of x and y, indicating that as one variable increases, the other decreases.

A relationship is a direct variation if the ratio of y to x is constant for all pairs of values.

A relationship is an inverse variation if the product of x and y is constant for all pairs of values.