Question 201029
y =  -x^2 +3,,,,,or,,,,y-3 =(-1) (x-0)^2
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remember  the  std  form  is  ,,,,,y-k = a (x-h)^2
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in  this  case  vertex(h,k)  is  at  (0,3)
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as  the  coeff "a"  is  negative,  the  parabola  points  down,  and  vertex  is  a maximum
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