# Online Math Dictionary: N

Easy to understand math definitions for K-Algebra mathematics
Just scroll down or click on the word you want and I'll scroll down for you!

 natural numbers negative numbers nonagon null set number number line numerals numerator

Natural numbers
The Natural numbers are:  { 1, 2, 3, 4, 5, 6, ... }
The natural numbers are the counting numbers without zero.

Negative numbers
Negative numbers are those that appear to the left of zero on the number line.

 NonagonA nonagon is a nine sided polygon.  The picture on the right is a regular nonagon since all the sides and angles are the same.  (congruent.)  For more info, check out Properties of Nonagons.

 Null setA null set is the same as an "empty set."  A null set is a set with no members (or elements).  The symbol for the null set is on the right.It can also be written as an empty set of set brackets:                                        {   }Putting the null set symbol inside the set brackets is a bad thing...  But, is a common mistake, so don't do it!

Number
A number represents the value or quantity of something...  Like how much money you have...  Or how many marbles you  have...  Or how tall you are.

Number Line
number line is an infinitely long line whose points match up with the real number system.

Numerals
A numeral is a symbol that represents a number.

 NumeratorA numerator is the top number in a fraction. For more info, check out my lessons on fractions.

 A B C D E F G H I no J's K L M N O P Q R S T U V W no X's no Y's no Z's