How do you find the vertex of this parabola #y=-x^2-2x-5#?

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Answer 1 · 2016-11-03T19:51:33

Please read the explanation for the steps leading to the vertex #(1, -8)#

For an equation of a parabola of the form #y = ax^2 + bx + c#, the x coordinate, h, of the vertex is:

#h = -b/(2a)#

In the given equation, #a = -1, and b = -2#, therefore:

#h = (-2)/(2(-1))#

#h = 1#

To obtain the y coordinate of the vertex, evaluate the function at h:

#y = -(1)^2 - 2(1) - 5#

#y = -8#

The vertex is at the point #(1, -8)#