Mishita Dharia - Quadratics

All relationships do not have to be linear and have graphs that are straight lines. Sometimes a graph may be a curve, which would suggest that it is a non-linear relationship.

 

In these cases, we would use a curve of best fit rather than a line of best fit to model this relation.

 

However, non-linear relationships are not all quadratic. Quadratic relationships are only those with constant second differences.

 

In a table of values, if the first differences of the y-value (dependent value) are constant, then the relationship is linear. However, if the first differences are not constant, but second differences are then the relationship is quadratic. If neither the first differences nor second differences are the constant then the relationship is neither linear nor quadratic.