Answer
Axis of symmetry: x=-1
Vertex: (-1,-3)
Work Step by Step
$y = 2x^{2} + 4x - 1 $
The standard form for a quadratic equation is
$y = ax^{2} + bx + c$ So a= 2, b= 4, and c= -1
Axis of symmetry:
The formula for axis of symmetry is
$x= \frac{-b}{2a}$
$x= \frac{-(4)}{2(2)}$
$x= \frac{-4}{4}$
x=-1
Vertex:
Plug in the x value of the axis of symmetry to find the y value of the vertex.
$y = 2x^{2} + 4x - 1 $
$y = 2(-1)^{2} + 4(-1) - 1 $
y= 2 - 4 - 1
y= -3
The vertex is (-1,-3)
