Let P and Q be the points of trisection of the line segment joining the points A (2, - 2) and B (- 7, 4) such that P is nearer to A. find the coordinate of P and Q.



As P and Q are the points of trisection so


AP = PQ = QB


consider


PB = PQ + PB


PB = AP + AP


PB = 2AP



i.e. P divides line joining the points A and B in a ratio 1 : 2


now we know that the coordinates of the points P(x, y) which divides the line segment joining the points A(x1, y1) and B(x2, y2), internally in the ratio m : n are



In this case we have


A(x1, y1) = (2, - 2)


B(x2, y2) = (- 7, 4)


m : n = 1 : 2



P(x, y) = (- 1, 0)


Now,


PQ = QB


i.e Q is the mid point of PB



[ As The mid - point of the line segment joining the points (x1, y1) and (x1, y1) is  




Coordinates of P = (- 1, 0) and 

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