How do you find the axis of symmetry and vertex point of the function: # y=x^2+6x-7#?

Question

3142 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-10-23T09:08:54

First you change this equation to complete square form;
y = #x^2# +6x -7

#(x^2 + 2*3x +3^2 -7 -3^2)#

#[(x^2 + 3) ^2 -(7 + 9)]#

#(x^2 + 3) ^2 -16# is in the form of #a(x-h)^2 +k#

where #a=1# , #h= -3# and #k = -16#

The vertex is given by #(h,k)#

So the vertex is #( -3,-16#

and the line of symmetry is given by #(x-h)=0#
So

x+3 = 0 is the axis of symmetry