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
$x=−b/2a$
$x=−(4)/2(2)$
$x=−4/4$
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)
