y=3x²+6x+1
to find the x value of the vertex, find the axis of symmetry which is -b/2a where a=3 and b=6,
so the axis of symmetry
=-6/2(3)
=-1
to find the y value of the vertex sub the axis of symmetry which is -1 back into the original equation.
y= 3(-1)²+6(-1)+1
y=-2
therefore the vertex is (-1,-2)