How do you find the vertex of #g(x)=-x^2+6x-8#?

1 Answer
Nov 1, 2016

Rearrange the equation into Vertex Form (or use the shortcut to find axis of symmetry and substitute x) .

Explanation:

To get the vertex for an equation your best bet is to convert the form into vertex form,which is #y=a(x-h)+k#. In vertex form #(h,k)# is the vertex.

The work to get an answer:
#y=-x^2+6x-8#
#y+8=-x^2+6x#
#y+8=-(x^2-6x)#
#y+8+9=-(x-3)^2#
#y=-(x-3)^2-17#

So the vertex is #(3,-17)#

PS; the shortcut is when the equation is in the form #y=ax^2+bx+c# is to make it #y=a(x-(-b/(2a)))^2+c/a# and just use the needed into to substitute it into it so #((-b/(2a)), c/a)# is your answer.