Respuesta :

Convert  to vertex form:-

y = (-4/9) (x^2 - 6x) + 12

y = -(4/9) [(x - 3)^2 - 9] + 12

y = (-4/9)(x - 3)^2 + 4 + 12

y = (-4/9)(x - 3)^2 + 16


So maximum height = 16 feet