Question

Identify the vertex for the graph of y = 2x2 + 8x − 3.

Answer 1

Vertex: (-2, -11)
Focus: ( -2 -87/8)
Axis of Symmetry: x = -2
Directrix: y = -89/8

X / Y
-4/ -3
-3/-9
-2/-11
-1/-9
0/-3

Answer 2

The vertex of the given parabola is (-2,-11).

Explanation:

The given function is

`y=2x^2+8x-3` .... (1)

The general for of a parabola is

`y=ax^2+bx+c` .... (2)

then the vertex of the parabola is

`(-(b)/(2a),f((-b)/(2a)))`

From (1) and (2), we get

`a=2,b=8,c=-3`

`-(b)/(2a)=-(8)/(2(2))=-2`

Put x=-2 in the given function.

`y=2(-2)^2+8(-2)-3=-11`

Therefore the vertex of the given parabola is (-2,-11).