Given equation of parabola, y2−4x−8y−12‌‌=0 ‌ or ‌‌‌y2−8y+16‌‌=4x+28 (y−4)2‌‌=4(x+7) ‌ Comparing with ‌Y2‌‌=4aX Y‌‌=y−4,a=1,X=x+7 parametric form of Y2=4aX X=at2,Y=2at ⇒‌x+7‌‌=t2,y−4=2t ‌ or ‌‌x‌‌=−7+t2,y=4+2t