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)

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