Q39 of 66 Page 7

If (0, - 3) and (0, 3) are the two vertices of an equilateral triangle, find the coordinates of its third vertex.(CBSE 2014)

Coordinates are A(0, -3) and B(0,3) and C(x, y)


Using distance formula =


⇒ AB = AC



On squaring both sides, we get


=


=


(1)


⇒ AB = BC



On squaring both sides, we get


=


=


(2)


On subtracting equation (2) from (1) we get




On substituting y = 0 in equation (1), we get





Therefore coordinates of third vertex are (), (),

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