: Using section formula, show that the points A (- 3, 1), B (1, 3) and C (- 1, 1) are collinear.
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Section Formula:
The co-ordinate of the point which divides the line segment joining the point and internally in the ratio are given by,
Let C(-1,1) divides the line segment joining A(-3,1) and B(1,3) in the ratio m:n
So, coordinate of C,
Since is not true.
Hence, the given point is not collinear