SOLUTION: Can someone please, please show me how to do this? Write the equation of the line which has y-intercept (0, 5) and is perpendicular to the line with equation y = –3x + 1. I got y

Algebra ->  Graphs -> SOLUTION: Can someone please, please show me how to do this? Write the equation of the line which has y-intercept (0, 5) and is perpendicular to the line with equation y = –3x + 1. I got y      Log On


   



Question 82966: Can someone please, please show me how to do this?
Write the equation of the line which has y-intercept (0, 5) and is perpendicular to the line with equation y = –3x + 1.
I got y = –3x + 5. AM i right, am I close to being right?

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Can someone please, please show me how to do this?
Write the equation of the line which has y-intercept (0, 5) and is
perpendicular to the line with equation y = –3x + 1.
I got y = –3x + 5. AM i right, am I close to being right?

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Your answer would have been correct if the word "perpendicular"
had been "parallel".

So you have confused "perpendicular" with "parallel"

Things to remember:

1.  Parallel lines have EQUAL slopes.
2.  Perpendicular lines have slopes which are formed by
    taking the reciprocal and changing the sign.

The slope of y = -3x + 1 is -3

Therefore a line which is perpendicular to it will have
the slope which is formed thusly:

Take -3.
Write it as -3%2F1
Invert it as -1%2F3
Change the sign and get 1%2F3

So the slope of a line PERPENDICULAR to the line whose
equation is y = -3x + 1 is 1%2F3

Now use the form:

     y = mx + b   where m = 1%2F3 and b = 5 

     y = 1%2F3x + 5

That is the PERPENDICULAR line's equation.

Edwin