Answer:
6, - 36 )
Step-by-step explanation:
Given a parabola in standard form
y = ax² + bx + c ( a ≠ 0 )
Then the x- coordinate of the vertex is
x = -
f(x) = x² + 12x ← is in standard form
with a = 1, b = 12, c = 0 , then
x = - = - 6
Substitute x = 6 into f(x) for corresponding value of y
f(6) = 6² + 12(- 6) = 36 - 72 = - 36
vertex = (6, - 36 )