Find the vertex, focus, axis, directrix and lotus - rectum of the following parabolas

y2 - 4y - 3x + 1 = 0

Given equation of the parabola is y2 - 4y - 3x + 1 = 0



y2 - 4y = 3x - 1


y2 - 4y + 4 = 3x + 3


(y - 2)2 = 3(x + 1)


Comparing with the standard form of parabola (y - a)2 = 4b(x - c) we get,


4b = 3



The vertex is (c, a) = (- 1, 2)


The focus is (b + c, a) =


The equation of the axis is y - a = 0 i.e, y - 2 = 0


The equation of the directrix is x - c = - b


Directrix is


Directrix is


Directrix is


Length of latus rectum is 4b = 3.


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