Q15 of 50 Page 220

Find the coordinate of the points which trisect the line segment joining the points A (2, 1, – 3) and B (5, – 8, 3).

Given; The line segment joining the points A (2, 1, – 3) and B (5, – 8, 3).

Let P(x1, y1, z1) and Q(x2, y2, z2) be the points which trisects the line segment.


⇒ P divides AB in the ratio 2:1;





⇒ Q divides AP in the ratio 1:1;





∴ (4, −5, 1) and (3, −2, −1) are the coordinate of the points which trisect the line segment joining the points A (2, 1, – 3) and B (5, – 8, 3).


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