The vertex of the parabola whose equation is  is

(, )

where  = the discriminant 

For ,

, ,  



So vertex = (,  ) = (, ) = (, ) = (, )

You mistyped that one because it should not have two equal signs. But it's 
done the same way.

If the second equal sign was supposed to have been a +, then 

vertex = (,)

If the second equal sign was supposed to have been a -, then 

vertex = (,)

Edwin