# How do you graph the function, label the vertex, axis of symmetry, and x-intercepts. y=-3x^2-12x-3?

May 23, 2015

$y = - 3 {x}^{2} - 12 x - 3$

Axis of symmetry:$x = \left(- \frac{b}{2} a\right) = \frac{12}{-} 6 = - 2$
Vertex:
x = -2
y = f(-2) = -12 + 24 - 3 = 9

x-intercepts: $y = - 3 \left({x}^{2} + 4 x + 1\right) = 0$

$D = {d}^{2} = 16 - 4 = 12 \to d = \pm 2 \sqrt{3}$

$x = - 2 + \sqrt{3}$
$x = - 2 - \sqrt{3}$