We know that
the equation of the vertical parabola in the vertex form is
<span>y=a(x-h)²+k
</span>where
(h,k) is the vertex of the parabola
if a> 0 then
the parabola opens upwards
if a< 0
then the parabola open downwards
in this problem we have
f(x)=−5(x+7)²<span>+6
</span>a=-5
so
a< 0 -------> the parabola open downwards
the vertex is the point (-7,6) is a maximum
the answer is the option
<span>a = -5, opens down</span>
see the attached figure
the equation of the vertical parabola in the vertex form is
<span>y=a(x-h)²+k
</span>where
(h,k) is the vertex of the parabola
if a> 0 then
the parabola opens upwards
if a< 0
then the parabola open downwards
in this problem we have
f(x)=−5(x+7)²<span>+6
</span>a=-5
so
a< 0 -------> the parabola open downwards
the vertex is the point (-7,6) is a maximum
the answer is the option
<span>a = -5, opens down</span>
see the attached figure
