Binary Operators   The Binary Operators are   +,  -,  x ,  and  

Commutative   An operation is commutative if the order does not matter. Addition and multiplication are commutative, subtraction and division are not.

Factor   A factor of a number is a number that divides that number exactly.

Integers   (with the 'g' pronounced like a 'j') includes the whole numbers, but extends the range to include negative numbers as well, i.e

.... -3, -2, -1, 0, 1, 2, 3, .........

Isosceles Triangle   has two equal sides, and therfore two equal angles.

Linear Equations  

Prime Numbers   are numbers with no factors other than 1 and the number itself.

Rational Numbers   are numbers that can be represented as a fraction. Integers come under this classification because, for example

\[ 12 = \frac{12}{1} \]

Reciprocal   The Reciprocal of a number is given by

\[ \mbox{reciprocal} = \frac{1}{\mbox{number}} \]

For example :

The reciprocal of 3 is $\frac{1}{3}$

The reciprocal of 0.362 = $\frac{1}{0.362}$ = 2.762