Question

The equation y2 + 4x + 4y + k = 0 represents a
parabola whose latus rectum is

Answer 1

Answer:

y

2

+4x+4y+k=0

y

2

+2×2y+4−4+4x+k=0

(y+2)

2

=−4x−k+4

(y+2)

2

=−4(x−

4

4+k

)

∴ Latus rectum =4 units

Answer 2

Answer:

y 2 +4x+4y+k=0

y 2+2×2y+4−4+4x+k=0(y+2) 2

=−4x−k+4(y+2) 2

=−4(x− 44+k)

∴ Latus rectum =4 units