Question

A line is perpendicular to another line if m2=[-1/m1], where m1 is the slope of the original line and m2 is the slope of the perpendicular line. Which of the following equations represents the line that passes through the point (1, –1) and is perpendicular to the line below?

http://media.education2020.com/evresources/2003-10-02-00-00_files/i0230003.jpg

Answer 1

What is the slope of that given line?

Answer 2

-1 right?

Answer 3

no, that's incorrect unfortunately

Answer 4

Start at the point (0,2)

How many units must you go down to get to the same horizontal level as (1,-1)?

Answer 5

-1/2

Answer 6

@jim_thompson5910

Answer 7

Start at the point (0,2)

How many units must you go down to get to the same horizontal level as (1,-1)?

Answer 8

It's not -1/2

Answer 9

The slope is not -1/2

Answer 10

http://media.education2020.com/evresources/2003-10-02-00-00_files/i0230004.jpg
http://media.education2020.com/evresources/2003-10-02-00-00_files/i0230005.jpg
http://media.education2020.com/evresources/2003-10-02-00-00_files/i0230006.jpg
http://media.education2020.com/evresources/2003-10-02-00-00_files/i0230007.jpg

Answer 11

@superdavesuper

Answer 12

the perpendicular slope is 1/3

Answer 13

m = 1/3 (perpendicular slope)

Since we want this perpendicular line to go through (1,-1), we know that

x = 1
y = -1

Answer 14

Plug all of this into y = mx+b, then solve for b

Answer 15

Tell me what you get

Answer 16

is it b. y=1/3x-1/3

Answer 17

What happens when you plug in x = 1 into that equation? What do you get for y?

Answer 18

y=1/3x-4/3

Answer 19

Same question: What happens when you plug in x = 1 into the equation y=1/3x-4/3? What do you get for y?

Answer 20

-1

Answer 21

so that verifies you have the right equation