x minus h, Squared.
over rx squared,
Plus y minus k squared.
over ry squared.
it all equals one!

Ellipses are one.
Bet they never told ya,
It works for Hyperbola,
The 2 radii,
rx and ry,
normally are Real,
but imagine if you will:

That Rx Squared OR Ry Squared just happen to be Negative,
The only way for this to be, a bumble bee, complexity.
The radius that has an i, don’t get to have no verticii.
But draw both radii to show, the box that holds the asymptotes,
now summoning your mortal strength, you’ll find that pesky focal length.
It’s longer than both radii, when we’re talkin’ Hyperboli!