graph:
y^2-4x=0.
how in the world do i graph this. and how do i know it's a parabola??
4 x = y^2
x = (1/4) y^2
for every x, there are two y values, positive and negative
x is never negative because y^2 is always +
when y = 0, x = 0
when y = +1 or -1, x = 1/4
when y = +2 or -2, x = 1
when y = +4 or -4, x = 4 etc
parabola open to the right, vertex at origin.