Question 314436
Complete the square to get the equation into vertex form, 
{{{y=a(x-h)^2+k}}}
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{{{y=2(x^2+4x)+5}}}
{{{y=2(x^2+4x+4)+5-8}}}
{{{y=2(x+2)^2-3}}}
The vertex is ({{{-2}}},{{{-3}}}).
The axis of symmetry is {{{x=-2}}}.
{{{ drawing( 300, 300, -5, 5, -5, 5, grid(1),circle(-2,-3,.3),blue(line(-2,-10,-2,10)),graph( 300, 300, -5, 5, -5, 5, 2(x+2)^2-3,2x^2+8x+5)) }}}