Question 440157
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Hi

Using the vertex form of a parabola, {{{y=a(x-h)^2 +k}}} where(h,k) is the vertex
f(x) = -x^2 + 6x   |Completing Square to find the Vertex
y = -[(x-3)^2 - 9]
y = -(x-3)^2 + 9      |represents parabola opening downward, a<0 
vertex Pt(3,9) f(3) = 9 is a maximum point
Domain: *[tex \LARGE \ \ x\ \in\ \mathbb{R}] and Range: {y|y &#8804; 9}