titik puncak grafik fungsi kuadrat y= -4x² +8x -3 adalah A. ( -1,-15 ) D. (1,1) B. ( -1,1 ) E. (1,9) C. ( -1,9 )

y = -4x² +8x -3
a = -4, b = 8, c = -3
Xpuncak = [tex] \frac{-b}{2a} = \frac{-8}{2.(-4)} = 1 [/tex]

Y puncak  = [tex] \frac{-D}{4a} = \frac{-(b^{2} - 4ac)}{4a} \\ = \frac{-(8^{2} - (4.(-4).(-3))}{4.(-4)} \\ = \frac{-(64 - 48)}{-16} \\ \frac{-16}{-16} = 1 [/tex]

jawaban D(1,1)