1. Remember that circle could be an equal sign.

2. In the check equations, each side of the equal sign is algebraically equivalent but cannot be verified exactly since the readings mi are obtained experimentally.

3. The quantities on each side of the equal sign (=) of the check equations are obtained from combinations of the linear equations of condition that are equivalent to one another algebraically.

4. Recently in some LaTeX documentation I noticed that there is a special LaTeX command for the symbol meaning "Corresponds to", which is similar to an equal sign with a hat on top