# The slope of a vertical line is __; the slope of a horizontal line is ____.

The slope of a line can be determined by using two points from which the line passes.

## Answer: The slope of a vertical line is infinity; the slope of a horizontal line is zero

Follow the explanation given below to find the answer.

**Explanation: **

We know that,

The slope formula of a line is given by m = tan α, where α is the angle made by the given line with the x-axis.

Now, a vertical line makes a 90° angle with the x-axis. Therefore, the slope of a vertical line is tan 90 = infinity.

A horizontal line is a line parallel to the x-axis. Thus, it is inclined at 0° with the x-axis. Therefore, the slope of a horizontal line is tan 0 = 0.

We can also verify the answer using the slope calculator.

Let's get an idea from the figure given below,