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Easy

Question

# The equation of the directrix of the parabola y^{2} + 4y + 4x + 2 = 0 is-

- x = – 1
- x = 1
- x = –
- x =

## The correct answer is: x =

### To find the equation of directrix.

+ 4y + 4x + 2 = 0

= – 4 [x – (1 / 2)]

Let y + 2 = Y and x – (1 / 2) = X

= – 4X

Here a = 1, the equation of the directrix is X = a.

x – (1 / 2) = 1

x = 3 / 2

Therefore, the equation of directrix is x = 3 / 2.

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