SOLUTION: Hello there, I have been trying to solve this question: Write the equation of the line which passes through (3, - 1) and is perpendicular to the line with equation 3y

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Question 1178342: Hello there,
I have been trying to solve this question:
Write the equation of the line which passes through (3, - 1) and is perpendicular to the line with equation 3y - x = 3
I know the correct answer is 3x + y = 8, but I just can't seem to get there. Any help would be great, thank you.

Found 3 solutions by mananth, josgarithmetic, ikleyn:
Answer by mananth(16946)   (Show Source):
You can put this solution on YOUR website!
Write the equation of the line which passes through (3, - 1) and is perpendicular to the line with equation 3y - x = 3
3y - x = 3
3y=x+3
y = (1/3)x +1
slope m = (1/3)
the slope of any perpendicular line is the negative reciprocal of the other
slope of perpendicular is -3 passing through (3, - 1)
y=mx+b
plug point and slope
-1 = -3(3) +b
-1= -9 +b
b=8
the equation is y = -3x+8

Answer by josgarithmetic(39617)   (Show Source):
You can put this solution on YOUR website!

Perpendicular to this line, slope would be .

That perpendicular line through point (3,-1):

-
This line,

Answer by ikleyn(52781)   (Show Source):
You can put this solution on YOUR website!
.

At this site, there is a group of lessons related to this class of problems
    - Find the slope of a straight line in a coordinate plane passing through two given points
    - Equation for a straight line having a given slope and passing through a given point
    - Solving problems related to the slope of a straight line
    - Equation for a straight line in a coordinate plane passing through two given points
    - Equation for a straight line parallel to a given line and passing through a given point
    - Equation for a straight line perpendicular to a given line and passing through a given point (*)
    - Advanced problems on finding equations for straight lines

    - OVERVIEW of lessons related to the slope of a straight line

The most relevant to your current problem is the lesson marked (*) in the list.
So start from this lesson.

But if you want to learn the subject in all its aspects, you need to learn all these lessons.

Consider them as your textbook, handbook, tutorials and (free of charge) home teacher.

SOLUTION: Hello there, I have been trying to solve this question: Write the equation of the line which passes through (3, - 1) and is perpendicular to the line with equation 3y - x