JEE Mains Model Paper 2

Since y = mx - 2am - am3 is a normal to the parabola y2 = 4ax taking a = 3 and m = -1 we get
y = -x - 2 (3) (-1) -3 (−1)2
⇒ x + y = 9 is a normal to the parabola y2 = 4ax
y = mx + a/m
If it represents the line x + y = 9, then
m = - 1 and a/m = 9 ⇒ a = - 9
So an equation of the required parabola is
y2 = 4 (-9) x or y2 = -36x