Question

Please help!! What is the vertex of the graph of the function below?

y = x2 + 8x + 12
A. (-4, 0)
B. (-2, -4)
C. (-4, -4)
D. (-2, 0)

Answer 1

C

Explanation:

To find the vertex, find the value -b/2a for the x value and then substitute it to find the y value of the vertex.

Here the equation y = x2 + 8x + 12 has a = 1, b = 8 and c = 12.

So -b/2a = -8/2(1) = -8/2 = -4.

Substitute f(-4) = (-4)^2 + 8(-4) + 12 = 16 + -32 + 12 = -4.

The vertex is (-4,-4).