# Precalculus Examples

,
Step 1
Find the value of the slope.
Step 1.1
Slope is equal to the change in over the change in , or rise over run.
Step 1.2
The change in is equal to the difference in x-coordinates (also called run), and the change in is equal to the difference in y-coordinates (also called rise).
Step 1.3
Substitute in the values of and into the equation to find the slope.
Step 1.4
Simplify.
Step 1.4.1
Simplify the numerator.
Step 1.4.1.1
Multiply by .
Step 1.4.1.2
Subtract from .
Step 1.4.2
Simplify the denominator.
Step 1.4.2.1
Multiply by .
Step 1.4.2.2
Step 1.4.3
Move the negative in front of the fraction.
Step 2
Find the value of the y-intercept.
Step 2.1
Substitute the value of into the slope-intercept form of the equation, .
Step 2.2
Substitute the value of into the slope-intercept form of the equation, .
Step 2.3
Substitute the value of into the slope-intercept form of the equation, .
Step 2.4
Rewrite the equation as .
Step 2.5
Simplify .
Step 2.5.1
Multiply .
Step 2.5.1.1
Multiply by .
Step 2.5.1.2
Multiply by .
Step 2.5.2