Four points A (6, 3), B(-3, 5), C(4, -2) and D(x, 3x) are given in such a way that, find x.

Key points to solve the problem:


The idea of distance formula- Distance between two points P(x1,y1) and Q(x2,y2) is given by- PQ =



Area of a ΔPQR – Let P(x1,y1) , Q(x2,y2) and R(x3,y3) be the 3 vertices of ΔPQR.


Ar(ΔPQR) =



Given, coordinates of the triangle as shown in the figure.


Also,


ar(ΔDBC) =


=


Similarly, ar(ΔABC)




24.5 = 28x – 14


28x = 38.5


x = 38.5/28 = 1.375 …ans


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