Question

What is the parabola’s line of symmetry?
y-axis
x-axis
x = p
x = -p

Answer 1

The parabola's line of symmetry is the x-axis.

Answer 2

y = 1/4p x²

Replace  x  with  −  x  and  y  with  − y  to check if there is x-axis, y-axis , or origin symmetry.  

Symmetric with respect to the y-axis