- #1

- 99

- 0

well i got [tex](x+6)^2 + (y+7)^2 + (z+1)^2-9^2[/tex] which is correct.

now for the next question:

Give an equation which describes the intersection of this sphere with the plane [tex]z=0[/tex].

i don't understand how to do the second question at all, can someone help?