Pick a point which lies inside the sphere x²+ y² - 4x - 6y + 8y -7 = 0

Centre of the sphere is c (2, 3, 4) and radius is 

$\mathrm{r}=\sqrt{4+9+16-(-7)}=6$

For point $\mathrm{P}(1,2,0),\mathrm{CP}=\sqrt{1+1+16}=\sqrt{18}<6$

So, point P(1, 2,0) lies inside the sphere. 

For other points, we have CP > 6.