SOLUTION: I'm not real sure what catergory I should have put this question in, but I'm really having a difficult time understanding parallel and perpendicular lines. here is the Question:

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Question 22849: I'm not real sure what catergory I should have put this question in, but I'm really having a difficult time understanding parallel and perpendicular lines.
here is the Question: Write an equation in slope-intercept form of a line with the following characteristics. Perpendicular to the graph of: y=3/2x-3.
my algebra book does not explain this well so if you could help me it would be greatly appreciated. Thanks. chris

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
If the given equation is y=3/2x -3, this means that the slope of the given line is 3%2F2. The slope of any line parallel to this line is also going to have a slope of 3%2F2, but that's another question. In this case, you need the slope of a line that is PERPENDICULAR to the given line. This slope would be the NEGATIVE RECIPROCAL of the slope 3%2F2 which would be -2%2F3.

The equation of a line in slope intercept form is y=mx%2Bb. So the slope of a line perpendicular to the given line must have slope of -2%2F3, so the equation would be y=+%28-2%2F3%29x%2Bb, where b could be any value, since no other restrictions were given. Usually the problem requires that the line pass through a given point, in which case you must also solve for b. But this too is another question!

Final answer, y=+%28-2%2F3%29x%2Bb, where b represents any number (which would also turn out to be the y intercept).

R^2 at SCC