Q36 of 149 Page 14

Determine the ratio in which the point (-6, a) divides the join of A(-3, 1) and B(-8, 9). Also find the value of a.

Here, given points are A(-3, 1) and B(-8, 9) and let the point dividing the line joining two points be C(-6,a).


Let the ratio be m:n



By section formula,


x = , y =


For point C(-6,a),


-6 = …(1)


And a = …(2)


Solving 1 for finding ratio between m and n,


-6 =


-6 (m + n) = -8m -3n


6m + 6n = 8m + 3n


∴ 2m = 3n


∴ =


∴ m : n = 3 : 2


Now solving for equation 2, where m = 3 and n = 2


a =


a =


∴ a =


∴ a =


∴ value of a is


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