Jawabanmu

2014-03-11T15:25:39+07:00
Puncak ( -2 , 6 ) melalui titik ( 0 , 4 )
nah gini , rumusnya y=a ( X-Xp )² + Yp
4 = a ( 0 + 2 )² + 6
4 = 4a+6
4a = -2
a= -1/2
nah  terus dimasukkin ke rumus awal lagi
y = -1/2 ( x + 2 )² + 6
  = -1/2 ( x²+4x+4) +6
  = -1/2x²-2x-2+6
  = -1/2x²-2x+4

nb : Xp = X puncak
       Yp = Y puncak
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