Operator & Identity Laws

In basic arithmetic the operator precedence is the order in which the mathematical operators are used in an equation. If it is not explicitly indicated with parentheses, any higher operators come first and then the division or multiplication operators which comes before the subtraction or addition operators. The comparison operators do not perform operative functions, but are used to compare one side of an equation with another. There are five of these operators:

= equal to
>= greater than or equal to
> greater than
<= less than or equal to
< less than

The identity laws establish simple rules for the identity and continuity of numbers and the use of zero in mathematical equations.

The five basic identity laws are for any real number a and b:

1) a + 0 = a
a plus zero equals a.

2) a x 1 = a
a times one equals a.

3) a x 0 = 0
a times 0 equals 0.

4) If a x b = 0, then either a = 0 or b = 0
If a times b equals 0, then either a or b is zero.

5) -(-a) = a
The negative of negative a equals a.