Koordinat titik balik grafik fungsi kuadrat f(×) =-ײ+4×+5

Kelas 10 Matematika
Bab Fungsi Kuadrat

f(x) = -x² + 4x + 5
a = -1; b = 4; c = 5

sumbu simetri
= -b/2a
= -4/(2 . -1)
= 2

f(2) = - 2² + 4 . 2 + 5
f(2) = -4 + 8 + 5
f(2) = 9

(2, 9)