Q. 185.0( 1 Vote )

# The length of the latus - rectum of the parabola 4y^{2} + 2x – 20y + 17 = 0 is

A. 3

B. 6

C. 1/2

D. 9

Answer :

Given equation of the parabola is 4y^{2} + 2x - 20y + 17 = 0

⇒ 4y^{2} - 20y + 17 = - 2x

⇒

⇒

⇒

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

⇒

We know that the that the length of the latus rectum is 4b.

∴The correct option is C

Rate this question :

The equation of the directrix of the parabola whose vertex and focus are (1, 4) and (2, 6) respectively is

RD Sharma - MathematicsWhich of the following points lie on the parabola x^{2} = 4ay?

The focus of the parabola y = 2x^{2} + x is

The length of the latus - rectum of the parabola x^{2} – 4x – 8y + 12 = 0 is

The length of the latus - rectum of the parabola 4y^{2} + 2x – 20y + 17 = 0 is

The vertex of the parabola (y – 2)^{2} = 16(x – 1) is

The length of the latus - rectum of the parabola y^{2} + 8x – 2y + 17 = 0 is

The directrix of the parabola x^{2} – 4x – 8y + 12 = 0 is