Harshit Singh
Last Activity: 4 Years ago
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Given that, the parabola equation is y2= -8x.
It is noted that the coefficient of x is negative.
Therefore, the parabola opens towards the left.
Now, compare the equation with y2= -4ax, we obtain
-4a= -8
⇒ a = 2
Thus, the value of a is 2.
Therefore, the coordinates of the focus = (-a, 0) = (-2, 0)
Since the given equation involves y2, the axis of the parabola is the x-axis.
Equation of directrix, x= a i.e., x = 2
We know the formula to find the length of a latus rectum
Latus rectum length= 4a
Now, substitute a = 2, we get
Length of latus rectum = 8
Thanks