Q17 of 50 Page 220

Let A (2, 2, – 3), B (5, 6, 9) and C (2, 7, 9) be the vertices of a triangle. The internal bisector of the angle A meets BC at the point D. Find the coordinates of D.

Given; A (2, 2, – 3), B (5, 6, 9) and C (2, 7, 9) are the vertices of a triangle, The internal bisector of the angle A meets BC at the point D.



⇒ ABC is an isosceles triangle and thus the internal bisector of the angle A meets BC at its midpoint.



∴ The coordinates of D is


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