Q49 of 66 Page 7

Find the ratio in which the point P(-1, y) line segment joining A ( -3,10) and B(6, -8) divides it. Also find the value of y.(CBSE 2013)

Here, given points are A ( -3,10) and B(6, -8) and the point dividing the line joining two points is P(-1,y).


Let the ratio be m:n



By section formula,


x = , y =


For point P(-1,a),


-1 = …(1)


And y = …(2)


Solving 1 for finding ratio between m and n,


-1 =


- (m + n) = 6m -3n


m + n = -6m + 3n


∴ 7m = 2n


∴ =


∴ m : n = 2 : 7


Now solving for equation 2, where m = 2 and n = 7


y =


y =


∴ y =


∴ y =


∴ value of y is

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