Both x and y are called variables as they represent numbers that do not have fixed values ( their actual values vary). Usually, the x-values can take any value, but the y-values depend on the value of the x-value.

• x- value is called the independent variable

• y-value is called the dependent variable

Example: The values of y are determined by the following relationship:

y = x + 2, add 2 to the value of the x-value

So the ordered pairs would be:

( x, y) or ( x, x+2)

So, when

• x = 1, y= 1 + 2 = 3 ---> Ordered Pair is ( 1, 3)

• x = 2, y= 2 + 2 = 4 ---> Ordered Pair is ( 2, 4)

• x = 3, y= 3 + 2 = 5 ---> Ordered Pair is ( 3, 5)

In a given set of ordered pairs, {(2, –3), (4, 6), (3, –1), (6, 6), (2, 3)}, ...

• the domain is a list/set of all the x-values domain: {2, 3, 4, 6}

• the range is the list/set of the y-values range: {–3, –1, 3, 6}

Ways of Representing Algebraic Relations