Q32 of 157 Page 737

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

– 1 = (m1x2 + m2x1)/ m1 + m2


– 1 = (m16 + m2(– 3))/ m1 + m2


– 1 = (6m1 – 3m2)/ m1 + m2


(6m1 – 3m2) = – m1 – m2


7m1 = 2 m2


m1: m2 = 2:7


y = (m1y2 + m2y1)/ m1 + m2


= (2x(– 8) + 7 × 10)/9


= (– 16 + 70)/9


= 54 / 9


y = 6


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