What is the vertex of the graph of this equation [tex]$y = -4x^2 - 16x - 12$[/tex]?

A. [tex](-2, -4)[/tex]
B. [tex](-2, 4)[/tex]
C. [tex](2, 4)[/tex]
D. [tex](2, -4)[/tex]



Answer :

To determine the vertex of the quadratic equation [tex]\( y = -4x^2 - 16x - 12 \)[/tex], we use the formula for the vertex of a parabola given by [tex]\( y = ax^2 + bx + c \)[/tex].

The vertex [tex]\((x, y)\)[/tex] of the parabola can be found using the following steps:

1. Find the x-coordinate of the vertex:

The x-coordinate of the vertex [tex]\( x_\text{vertex} \)[/tex] is given by
[tex]\[ x = \frac{-b}{2a} \][/tex]
where [tex]\( a = -4 \)[/tex] and [tex]\( b = -16 \)[/tex].

Substituting the values of [tex]\( a \)[/tex] and [tex]\( b \)[/tex]:
[tex]\[ x = \frac{-(-16)}{2(-4)} = \frac{16}{-8} = -2 \][/tex]

2. Find the y-coordinate of the vertex:

Substitute [tex]\( x = -2 \)[/tex] back into the original equation to get [tex]\( y_\text{vertex} \)[/tex]:
[tex]\[ y = -4(-2)^2 - 16(-2) - 12 \][/tex]

Calculate each term step-by-step:
[tex]\[ -4(-2)^2 = -4 \times 4 = -16 \][/tex]
[tex]\[ -16(-2) = 32 \][/tex]
[tex]\[ -16 + 32 - 12 = 4 \][/tex]

Therefore, the coordinates of the vertex are [tex]\((-2, 4)\)[/tex].

The correct answer is:
[tex]\[ \boxed{(-2, 4)} \][/tex]