We can create equations to use as tools to describe nature.

It is possible to treat the equation using perturbation theory.

The equations used to create the model establish consistent relationships among dramatic elements.

To call the equations used in statistics 'laws of nature' is a misnomer.

The Institute of Medicine equation uses a different approach to most others.

From here we can solve the equation using the above definition:

Further representations for can be found from the above equations using the replacement .

The above equations use a linear relationship between flow speed squared and pressure.

We can solve the eikonal equation using the method of characteristics.

This can be done by setting an equation using the brightness (in linear units) of each magnitude.