tentukan titik balik daru grafik fungsi y=1/3 x² + 5x-9 Tolong dijawab ya kak. Tq :D

y=1/3 x² + 5x-9

Xp=-b/2a =-5/(1/3)=-15
Yp=D/-4a
=b^2-4ac/(-4a)
=25-4(1/3)(-9)/-4(1/3)
=37/(-4/3)
=111/-4

(-15,-111/4)
maaf jika salah semoga membantu