Warm Up

a) Graph y + 3= 2(x + 1) b) What is the slope & the y-intercept?

Homework Check 4.11

Parallel and Perpendicular Lines

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From our discovery worksheet we found that if two lines have the same slope, then they are parallel.

1) What is the slope of a line that is parallel to the line y=4x-7?

2) What is the slope of a line that is parallel to the line y = -1/2x – 4?

3) Write the equation of the line parallel to y = -2x + 1 that has a y-intercept of -4.

4) Write the equation of the line parallel to y = 1/2x – 6 that has a y-intercept of 2.

5) Find the equation of the line parallel to y=3x+6 passing through the point (-1,9).

You try!Write an equation for the lines parallel to the given lines and passing through the given points.

6) y=1/2x-4 (4,2)

7) y=-2x+3 (1,2)

8) Are the lines y = -2x + 4 and 5x + 10y = 3 parallel ?

9) Are the lines -3x + y = 4 and -6x + 2y = -1 parallel?

Perpendicular Lines

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From our discovery worksheet, we saw that perpendicular lines have slopes that are negative reciprocals of each other.

What is the negative reciprocal of each slope?

a) 1 b) -5

c) 1/3 d) -2/5

1) What is the slope of a line that is perpendicular to the line y=-3x-7?

2) What is the slope of a line that is perpendicular to the line y = 1/2x – 4?

3) Write the equation of the line perpendicular to y = -3x + 1 that has a y-intercept of 5.

4) Write the equation of the line perpendicular to y = 2/3x – 1 that has a y-intercept of -7.

5) Find the equation of the line perpendicular to

y = x+6 passing through the point (2,-3).

You try!

Write an equation for the lines perpendicular to the given lines and passing through the

given points.

6) y = -x + 1 (2,-3)

7) y = 2x + 4(4,2)

8) Are the lines 2x + y = 4 and -3x + 6y = 1 perpendicular ?

9) Are the lines 3x + 4y = 5 and 6x + 8y = -1 perpendicular?

Coming up….

HW 4.12

Unit 4 Test – Friday!

Tutoring today!