Prove Slope of Parallel and Perpendicular Lines

Common Core: HSG-GPE.B.5

Proof -- slopes of parallel lines are equal & slopes of perpendicular lines are negative reciprocal
Prove two theorems about slopes
1) If two straight lines are parallel, then their slopes are equal.
2) If two straight lines are perpendicular, then the product of their slopes is - 1.

Find the equation of a line parallel or perpendicular to a given line that passes through a given point.

Equations of Parallel and Perpendicular Lines.

Find the Equation of a Line Parallel to a Given Line Passing Through a Given Point.
This video provides an example of how to find the equation of a line that is parallel to a given line in slope-intercept form passing through a given point. This video uses slope-intercept form and point-slope form to find the equation of the line.



Ex 2: Find the Equation of a Line Perpendicular to a Given Line Passing Through a Given Point
This video provides an example of how to find the equation of a line that is perpendicular to a given line in slope-intercept form passing through a given point. This video uses point-slope form to find the equation of the line.

Slope and Equations of Lines through Points
This Demonstration help students practice determining equations of lines given a pair of points, or the line parallel or perpendicular to a given line through a given point. It also gives students a chance to see the relationships between these lines and points.

Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

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