Q4 of 53 Page 115

Point P is the centre of the circle and AB is a diameter. Find the coordinates ofpoint B if coordinates of point A and P are (2, -3) and (-2, 0) respectively.

According to the mid point theorem the coordinates of the point P(x,y) dividing the line formed by A(a,b) and B(c,d) is given by:




In the given question A = (1,-3) and midpoint P is (-2,0).


Let coordinates of B be (c,d)


Then,



And



Solving for c and d, we get


-4 = 2 + c


c = -6


d = 3


Hence the coordinates of point B are (-6,3).


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