Slopes of Parallel and Perpendicular Lines
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Objective
I can determine if two lines are parallel, perpendicular, or neither by analyzing their slopes.
Part 1 of 4
Warm-up video
Kayla Jones · 5:24
We don't generate video — this one is by Kayla Jones on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
Parallel lines have the same slope but different y-intercepts, meaning they never intersect.
- 2
Perpendicular lines intersect at a 90° angle and have negative reciprocal slopes.
- 3
To find the negative reciprocal of a slope, flip the fraction and change the sign.
Part 3 of 4
Practice
10 questions
What is the relationship between the slopes of two parallel lines?
What is the relationship between the slopes of two perpendicular lines?
Part 4 of 4
Exit ticket
Quick comprehension check
“Line A has the equation y = 3x + 5. Line B has the equation y = -⅓x + 2. Are lines A and B parallel, perpendicular, or neither? Explain your answer.”
Sample answer included in the free materials
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Teacher Guide
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