How do you find the vertex of a parabola #f(x) = -x^2 - 2x#?

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Answer 1 · 2018-03-18T13:58:25

The vertex is (-1, 1)

The equation is in standard form

Standard form of a parabola:
#f(x)=ax^2+bx+c#
#-1# would be a and #-2# would be b in this equation.

To find the vertex, do #(-b)/(2a), f(-b/(2a))#.

#2/(2*-1)#

#2/-2#

#-1#

#f(-1)=-(-1)^2-2*-1#

#f(-1)=-1+2#

#f(-1)=1#

The vertex is (-1, 1)