$(\frac{x}{3}{)}^2-(\frac{y}{2}{)}^2-(\frac{z}{7}{)}^2=1$

$-(\frac{x}{3}{)}^2-(\frac{y}{2}{)}^2+(\frac{z}{7}{)}^2=1$

$-(\frac{x}{3}{)}^2-(\frac{y}{2}{)}^2+(\frac{z}{7}{)}^2=0$

$-(\frac{x}{3}{)}^2+(\frac{y}{2}{)}^2=\frac{z}{7}$

a$.$ cone on $z$ axis

b$.$ cone on y axis

c$.$ hyperboloid of one sheet

d$.$ elliptic paraboloid on $z$ axis

e$.$ hyperboloid of two sheets