**Introduction :**

Before seeing algebra undefined we have to know what is undefined. Undefined is nothing but which we can’t determine the value. In algebra undefined we are having two things. One id algebra slope, anther one is algebraic fraction. If a line is vertical or parallel to y – axis or perpendicular to x - axis then its slope is undefined. If the denominator of the fraction is 0 then it is an algebra undefined fraction.

## Algebra undefined examples using slope:

**Example 1:**

Find the slope between the points. (2, 8) and (2, 2)

**Solution:**

We know slope of line if the points given = `(y2 - y1) / (x2 - x1)`

Here (x_{1}, y_{1}) = (2, 8) and (x_{2}, y_{2}) = (2, 2)

So slope of the line = `(2 - 8) / (2 - 2)`

So slope of the line = **undefined.**

The graph will be like the following

**Example 2:**

Find the slope between the points. (5, 6) and (5, 9)

**Solution:**

We know slope of the line if the points given = `(y2 - y1) / (x2 - x1)`

Here (x_{1}, y_{1}) = (5, 6) and (x_{2}, y_{2}) = (5, 9)

So slope of the line = `(9 - 6) / (5 - 5)`

So slope of the line = **undefined.**

## Algebra undefined examples using fraction:

**Example 1:**

Find the value of x from the given fraction which makes the fraction is undefined.`5 / (9 + x)`

**Solution:**

Given fraction is `5 / (9 + x)`

To find the undefined value of x we have to equate the denominator to 0.

So we get 9 + x = 0

From this we get x = -9.

So x = -9 is the undefined value of x.

**Example 2:**

Find the value of x from the given fraction which makes the fraction is undefined.`2 / (2 - x)`

**Solution:**

Given fraction is `2 / (2 - x)`

To find the undefined value of x we have to equate the denominator to 0.

So we get 2 - x = 0

From this we get x = 2.

So x = 2 is the undefined value of x.

From the above we can understand how to do the algebra undefined.