Question

Identify the vertex for the graph of y=3x^2+12+5.

(2,41)
(2,35)
(-2,-31)
(-2,-7)

Answer 1

The vertex would be D) (-2, -7)

Explanation:

To find the vertex , start by find the x-value. For this we can use the equation below.

x = -b/2a

In which a is the coefficient of x^2 and b is the coefficient of x.

x = -b/2a

x = -(12)/2(3)

x = -12/6

x = -2

Now that we have x, we find y by plugging -2 in for each x.

y = 3x^2 + 12x + 5

y = 3(-2)^2 + 12(-2) + 5

y = 3(4) - 24 + 5

y = 12 - 24 + 5

y = -7