Answer
$x^2=20y$
Work Step by Step
Opens upwards. It is a parabola with vertical axis.
Focus: $F(0,p)$
Vertex: $V(0,0)$
$p$ is a positive number because the focus is on the positive y-axis. The focus is above the vertex.
Distance between the focus and the vertex: $p-0=p$
$p=5$
Equation: $x^2=4py$
$x^2=4(5)y$
$x^2=20y$