[math]\frac{x^2}{4}+y^2-\frac{z^2}{9}=-1[/math]
[math]\frac{x^2}{4}+y^2=\frac{z^2}{9}[/math]
[math]\frac{x^2}{4}+y^2-\frac{z}{9}=0[/math]
[math]\frac{x^2}{4}+y^2-\frac{z^2}{9}=0[/math]
[math]\frac{x^2}{4}+y^2-\frac{z^2}{9}=0[/math]
[math]\frac{9x^2}{4}-9y^2=z[/math]
[math]\frac{9x^2}{4}-9y^2=z[/math]
[math]\frac{x^2}{4}+y^2+\frac{z^2}{9}=1[/math]adfa
[math]\frac{x^2}{4}+y^2+\frac{z^2}{9}=1[/math]adfa