According to aaamath.com:

An equation is a mathematical statement that has two expressions separated by an equal sign.

The expression on the left side of the equal sign has the same value as the expression on the right side.

One or both of the expressions may contain variables.

Solving an equation means manipulating the expressions and finding the value of the variables.

Therefore I have determined:

*The greatest distance between two people is indifference towards one another.