Question 635443
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,
Note: the vertex form of a Parabola opening up(a>0) or down(a<0), {{{y=a(x-h)^2 +k}}} 
where(h,k) is the vertex  and  x = h  is the Line of Symmetry
f(x)= 1/4(x+9)²+1 
+ The vertex is  (-9,1) parabola opens Upward:  a = 1/4 > 0
+ The line of Symmetry is  x = -9
+ What is the max/min value of f(x): min value is 1 
+ Is the value of, f (-9)=1, a maximum or a <u>minimum</u>
{{{drawing(300,300,   -20,10,-10,10, blue(line(-9,10,-9,-10)),  
 grid(1),
circle(-9, 1,0.4),
graph( 300, 300, -20,10,-10,10,0,.25(x+9)^2 + 1))}}}