<Dd> x 2 = 2 R y (\ displaystyle x ^ (2) = 2Ry) (Equation 1) </Dd> <P> Compare this with the parabola: </P> <Dl> <Dd> x 2 = 4 f y (\ displaystyle x ^ (2) = 4fy) (Equation 2) </Dd> </Dl> <Dd> x 2 = 4 f y (\ displaystyle x ^ (2) = 4fy) (Equation 2) </Dd>

Is the line that runs through the focus perpendicular to the directrix