Q16 of 49 Page 1

Find the ratio in which point C (-1, y) lying on the line segment joining points A (-3, 10) and B (6, -8) divides it. Also find the value of y.

Let the point C (x, 0) divide the line segment A (3, -3) and B (-2, 7) in the ratio k: 1.


The co-ordinates of C is given by,





Now, according to the given figure,



⸫ = -1


⇒ 6k – 3 = -1 (k + 1)


⇒ 6k – 3 = -k – 1


⇒ 7k = 2


⸫ k =


⸫ The ratio = k: 1 = : 1 = 2: 7


Now,


⇒ = y


⇒ y ( =


⇒ y


⇒ 9y = 54


⸫ y = 6


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