Lines and Slope: Finding Slope

The slope of a line represents the direction of a line on the coordinate plane.

-  A coordinate plane contains two perpendicular number lines. The horizontal line is and the vertical line is . The point at which the two axes intersect is called the origin. An ordered pair (, ) shows the location of a point.
-  A line on a coordinate plane can be drawn by connecting two points.

-  To find the slope of a line, we need the equation of the line or two points on the line.
-  The slope of a line with two points A () and B () can be found by using this formula:
-  The equation of a line is typically written as where is the slope and is the -intercept.

Examples:

Example 1.  Find the slope of the line through these two points:
.
Solution: . Let .
(Remember, you can choose any point for and ).
Then:
The slope of the line through these two points is .

Example 2.  Find the slope of the line with equation
Solution: When the equation of a line is written in the form of , the slope is . In this line: , the slope is .