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yet another co-ordinate geometry question

hey all

just a quick question, if someone could guide me through rather than give the answer, will be much appreciated!
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Find the vertices of teh triangle ABC whose sides are given by the lines
AB: x-2y=-1
BC: 7x+6y=53
AC: 9x+2y=11

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as far as i understand, i have to find the points of intersection of AB with BC and BC with AC, but you cant simultaneously solve them nicely! lol

any help would be appreciated!
thank you!
Reply 1
It doesn't look too bad.

Just take two equations at a time. The first two, for example:

Multiply the first by 3 and add to the second so the y cancels...
=> 10x = 50
x = 5

=> y = 3 (by subbing into either of the two equations)
So AB and BC meet at the point B(5,3)

And continue like that for the others.
Reply 2
thank you
soo bloody simple, yet i couldnt figure it out. :frown:

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