Graph a horizontal or vertical line

key notes:

The graph of x=3  is a vertical line. every x value is 3, including the x-intercept

Graphing a Horizontal Line:

1. A horizontal line is parallel to the x-axis.
2. The equation of a horizontal line is of the form y = k, where k is a constant.
3. The y-coordinate remains constant for all points on a horizontal line.
4. To graph a horizontal line, locate the y-intercept (where it crosses the y-axis) and draw a straight line through that point.

Graphing a Vertical Line:

1. A vertical line is parallel to the y-axis.
2. The equation of a vertical line is of the form x = h, where h is a constant.
3. The x-coordinate remains constant for all points on a vertical line.
4. To graph a vertical line, locate the x-intercept (where it crosses the x-axis) and draw a straight line through that point.

Example:

• Graph the equation y = 3. It represents a horizontal line where every point on the line has a y-coordinate of 3.

Important Tips:

1. Remember that a horizontal line has a slope of 0, and a vertical line has an undefined slope.
2. Pay attention to the intercepts (x-intercept for vertical lines, y-intercept for horizontal lines) when graphing.
3. Use a ruler to ensure straight lines when drawing the graph.

Applications:

1. In real-world problems, horizontal and vertical lines might represent constant values or limits in various contexts.
2. In physics, vertical lines can represent time while horizontal lines can represent constant values like velocity.

Learn with an example

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