emath turms conix

(x-h)^2+(y-k)^2=r^2

circle

(x-h)^2/a^2+(y-k)^2/b^2=1

elipse

(x-h)^2=4p(y-k)

(y-k)^2=4p(x-h)

parabola

(x-h)^2/a^2-(y-k)^2/b^2=1

hyperbola