SOLUTION: Graph 9x^2+y^2=9 Give the coordinates of the foci

Question 188878: Graph 9x^2+y^2=9
Give the coordinates of the foci
Answer by Mathtut(3670) (Show Source): You can put this solution on YOUR website!

:
c=(+-)sqrt(8)
:
c=(+-)2sqrt(2)
:
foci are at (0,+2sqrt(2)) and (0,-2sqrt(2))