Amath questions

Let A is the point on the x-axe and B is the point on the y axe
then if the point P is (a,b) , then A becomes (a,0) and B becomes (0,b)
Since AB passes through M (3,4), the slope of AB and AM should be the same
So
(0-b)/(a-0)=(0-4)/(a-3)
b/a=4/(a-3)
4a=ab-3b
change back P(a,b) to (x,y)
the equation of the locus of P is
4x=xy-3y


2008-11-23 19:16:13 補充：
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