The length of the latus-rectum of the parabola x2−4x−8y+12=0 is
4
6
8
10
Given : x2−4x−8y+12=0
⇒ (x−2)2−8y+8=0
⇒ (x−2)2=8y−8=8(y−1)
Let X=x-2,Y=y-1
∴ X2=8Y
∴ Length of the latus rectum=4a=8 units