Answer:
D (-2,15)
Step-by-step explanation:
To find the vertex from the standard form of the equation, use the formula x = -b/2a. Then substitute the x value into the equation to find the y value.
Here a = -3 and b = -12.
So x = -(-12) / 2(-3) = 12 / -6 = -2.
Substitute x = -2 and solve for y.
y = -3(-2)^2 - 12(-2) + 3
y = -3(4) + 24 + 3
y = -12 + 24 + 3
y = 12 + 3
y = 15
