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Chen
Nov17-03, 03:31 PM
(I don't study math in English so I'm not sure what the exact terms are... please bear with me. :))

If you have this line:
y = mx + n
m is the inclination of the line, right? And I have this equation to find m:
2m + 1 = 2m + 4 (I'm finding a line between two other lines that divides the angle in half)
Obviously no m can solve that equation - this means that the line is reall of the form:
x = [a number]

Am I correct?

Hurkyl
Nov17-03, 04:14 PM
Knowing only what you've written here, my best guess is that you're correct. What was the entire problem?


P.S. we would call m the slope of the line.

Chen
Nov17-03, 04:22 PM
The whole problem was this:

You have a triangle ABC, with BC on the line:
3x - 4y + 37 = 0 (BC)
And then you also have the equations for the two lines that divide the angles B and C of the triangle:
2x - y + 3 = 0 (BE)
x + 7y - 4 = 0 (CF)

I solved it by finding the slope of both AB and AC, and then finding B and C, and then finding the equations of AB and AC, and finally finding the coordinates of A.

To find m (slope of AB) I did this: (based on the given that the angle between AB and BE is the same as the angle between BE and BC)
(2 - m) / (1 + 2m) = (3/4 - 2) / (1 + 6/4) = -1/2
-4 + 2m = 1 + 2m
-4 = 1

And from this I deduced that the line AB is perpendicular (sp?) to the X axis. I found B to be (5, 13) and since it is on the AB line I figured that AB was x = 5.

Thanks for the help. :-)