**Let’s see what happens when we try to calculate the slope of a vertical line.**

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**Choose any two 2 points on the line: (3,1) and (3, -2) **

**Find slope using the slope formula: **

**Step 1**** Label (3, 1) and (3, -2)**

**Step 2**** Plug the numbers into the formula**

**Finding slope graphically**

## Slope of a Horizontal Line

## Slope of a Verticall Line

### Slope of a Line

**The slope of a**** horizontal line ****is zero. A horizontal line has a horizontal change but the vertical change is zero. The rise/run formula for slope always yields zero since rise = 0.**

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**Let's look at an example:**

**The y intercept of a ****Horizontal Line ****is calculated using the **

**y = mx + b ( The slope will be the where the line intercepts the y axis)**

**y = 0x + 2**

**y = 2**

**If the line crosses the y axis at -3 **

**y=0x -3**

**y=-3**

**A line that is ****vertical**** does not have a slope A vertical line has a "rise", but no "run". The rise/run formula for slope always has a zero denominator and is undefined.**

Because a Horizontal line always has a rise of 0 it will always have a slope of 0

Video Example of finding slope using the slope formula of line passing through (3.1) and (3 -2)