# Chapter 3 - Introduction to Graphing - Study Summary - Practice Exercises: 9

The slope of the line is zero.

#### Work Step by Step

RECALL: (1) The slope of the horizontal line $y=k$ is zero. (2) The slope of the vertical line $x=h$ is undefined. $y=10$ is a horizontal line. Thus, its slope is zero

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.