2.7Equations of Parallel and Perpendicular Lines
Quick Answer
To write a parallel line: use the same slope, substitute the given point into y = mx + b to find b. To write a perpendicular line: use the negative reciprocal slope, then find b the same way.
Essential Question
How do we write the equation of a line that is parallel or perpendicular to a given line and passes through a specific point?
Learning Goals
- 1Write the equation of a line parallel to a given line through a given point.
- 2Write the equation of a line perpendicular to a given line through a given point.
- 3Use slope-intercept and point-slope forms.
- 4Verify that the written equation satisfies the given conditions.
Key Vocabulary
Slope-intercept form
y = mx + b, where m is slope and b is y-intercept.
Point-slope form
y − y₁ = m(x − x₁), used when a point and slope are known.
Full lesson content coming soon
Worked examples, guided practice problems, a workbook, quiz, and downloadable PDF resources will be added to this lesson in Phase 2. The learning goals and vocabulary above reflect the complete lesson scope.