The vertices of a triangle ABC are A(1,2), B(4,6) C(6,14). AD is the bisector of the angle A meets BC at D. Find the coordinates of the point D.

As the angle bisector divides the sides in a proportional ratio.


So ABAC=BDCD
Hence AB = (4-1)2 + (6-2)2 =5
And AC = (6-1)2 +(14-2)2=13
So AB/AC = 5/13
So point D(x,y) divides BC in the ratio of 5:13
Hence from internal division formula
x = 5×6 + 13×45+13,  y =5×14 +13×65+13
So x = 82/18 , y = 148/18
So coordinate of D is (82/18, 148/18)

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