The general form for a line is
where and are integers.
How does it work? Video
Using either the slope intercept form () or the general form () we can calculate all the critical values of a straight line. These are: the intercept, the intercept and the slope.
Example 1: convert to form:
Example 2: convert to general form:
Finding the y intercept
The y intercept is the point where the line cuts the y-axis. The x coordinate is zero. To find the y intercept, we substitute for .
Example 3: Find the y intercept of the line
Finding the x intercept
The x intercept is the point that is on the line and on the x axis. The y coordinate is zero. To find the x intercept, we substitute for .
Example 4: Find the x intercept of the line
Example: Video (3:31 mins)
5 Examples for this applet: Video (16 mins)
Examples for this applet on a pdf: Examples x y intercepts slope general form
Calculate the x and y intercepts and the slope. Rewrite the equation in the alternate form. Use fractions or terminating decimals, don’t round decimals.