titik puncak grafik fungsi kuadrat y=-4²+8x-3adalah

d/-4a=b²-4ac/-4a
       = 8²-4(-4)(-3)/-4(-4)
       = 64-48/16
       = 16/16
       = 1

a=-4, b=8, c=-3
-b/a, (b2-4ac)/-4a
= -8/-4, (8x8 -4 x(-4)x(-3)) /-4x(-4)
= -2 , (64-48)/16
= -2 , 1