Which is the equation of the axis of symmetry of the graph of y is equal to negative 3 times open paren x minus 6 close paren squared plus 5 ?

The equation is in vertex form, y = a(x − h)² + k, whose axis of symmetry is x = h. Here, (x − 6) means h = 6, so the axis is x = 6, choice D.

AI-written and checked against the verified answer.