# Precalculus Examples

,
Step 1
Use the slope-intercept form to find the slope.
The slope-intercept form is , where is the slope and is the y-intercept.
Using the slope-intercept form, the slope is .
Step 2
The equation of a perpendicular line must have a slope that is the negative reciprocal of the original slope.
Step 3
Find the equation of the perpendicular line using the point-slope formula.
Use the slope and a given point to substitute for and in the point-slope form , which is derived from the slope equation .
Simplify the equation and keep it in point-slope form.
Step 4
Write in form.
Solve for .
Simplify .
Rewrite.
Simplify by adding zeros.
Apply the distributive property.
Combine and .
Multiply .
Multiply by .
Combine and .
Move all terms not containing to the right side of the equation.
Add to both sides of the equation.
To write as a fraction with a common denominator, multiply by .
Combine and .
Combine the numerators over the common denominator.
Simplify the numerator.
Multiply by .