A16­6ParallelPerpendicularLines.notebook
February 19, 2015
Algebra 1
Ch.6 Notes Page 31
P31 6­6 Parallel and Perpendicular Lines
Sep 2­8:31 AM
Parallel Lines
Parallel lines are lines that never intersect (touch).
y = 2x + 1
y = 2x + 3
Nov 19­6:49 AM
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A16­6ParallelPerpendicularLines.notebook
February 19, 2015
Are Lines Parallel???
Write the Equations in Slope­Intercept Form
If the slopes are the same, they are parallel
If the slopes are different, they are not parallel
y = 2x + 4
3x + 4y = 12
Nov 27­8:59 AM
Writing Equations of Parallel Lines
Write the equation for the line that goes through the point (3, 12) and is parallel to y = 2x + 3
Write the equation for the line that goes through the point (2, ­6) and is parallel to y = 3x + 9
Nov 27­8:59 AM
2
A16­6ParallelPerpendicularLines.notebook
February 19, 2015
Perpendicular Lines
Perpendicular lines touch at a 90 degree (right) angle.
Their slopes are reciprocals.
y = 4x + 2
y = ­1/4x ­ 1
Nov 27­8:59 AM
Writing Equations for Perpendicular Lines
Write the equation of a line that is perpendicular to y = 5x + 3 and goes through the point (0, ­2)
Find the Negative Reciprocal of the Slope.
Substitute the new slope and point into the equation and solve.
Nov 27­8:59 AM
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A16­6ParallelPerpendicularLines.notebook
February 19, 2015
Nov 27­8:59 AM
HW34 6­6 P346 #1­9,13,15,19­24,26,27,31­33,40
Please put your name and class period at the top of the homework.
Also include the homework number.
Sep 30­2:29 PM
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