Tolong !!! Pertanyaan yang agak sulit

Fungsi Kuadrat

f(x) = 3x² + 5x + 4
a = 3 ; b = 5 ; c = 4
D = b² - 4ac = -23

x = -b/2a = -5/6

y = -D/4a = 23/12

Puncak = (x,y) = (-5/6 , 23/12)

Opsi : D