Q48 of 149 Page 14

A point P divides the line segment joining the points A (3, -5) and B (-4, 8) such that . If P lies on the line x + y = 0, then find the value of k.

Here given points are A (3, -5) and B (-4, 8) .


Let point P be (x, y) which divides AB in ratio of k:1, also point P lies on line x + y = 0



By section formula,


x = , y =


For point P on the line joined by the points A and B.


x = , y =


Putting in given equation,


+ =0


∴-4k +3 +8k -5 = 0


∴ 4k = 2


∴ k =


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