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.