# What is the slope of a line parallel to the x-axis?

Sep 18, 2014

The $x$-axis is a horizontal line with the equation $y = 0$.

There are an infinite number of lines that are parallel to the $x$-axis, $y = 0.$

Examples: $y = 4$, $y = - 2$, $y = 9.5$

All horizontal lines have slope of 0.

If lines are parallel then they have the same slope.

The slope of a line parallel to the $x$-axis is 0.