Help please

(-1,3)

x - y^2 + 6y  = 8      rewrite as

x  =  y^2 - 6y  + 8     

This one  is a little different  from the "normal" vertical parabola

It turns sideways and opens to the right

The y coordinate of the vertex is given by 

- (-6) /2(1)  =  3

So  the x coordinate of the vertex  is

x  =  (3)^2 - 6(3) + 8

x  = 9 - 18 + 8

x  = -1

So......the vertex  is    (-1, 3)

Here's a graph  ; https://www.desmos.com/calculator/wicxhszt9d