# What are the vertex, axis of symmetry, maximum or minimum value, domain, and range of the function y=-x^2-4x+3?

May 12, 2015

x of the vertex and axis of symmetry:

$x = - \frac{b}{2} a = \frac{4}{-} 2 = - 2.$ y of vertex:

$y = f \left(- 2\right) = - 4 + 8 + 3 = 7$

Since a = -1, the parabola opens downward, there is a max at (-2, 7)

Domain: (-infinity, +infinity)

Range ( -infinity, 7)