Line A has the equation y = 3x + 5. Line B has the equation y = 3x - 2. Are these lines parallel, perpendicular, or neither? Explain your reasoning.

The lines are parallel because they have the same slope (3) but different y-intercepts (5 and -2).

Slopes of Parallel and Perpendicular Lines

Name: Slopes of Parallel and Perpendicular Lines
Author: Insta~Lesson

9th Grade · Math · 45 min

I can determine if two lines are parallel, perpendicular, or neither by analyzing their slopes.

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.

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