Question

Which equation when graphed has a maximum value at x = −2? A) y = −x2 − 20x − 16, B) y = −x2 − 16x − 12, C) y = −4x2 − 20x − 16, D) y = −4x2 − 16x − 12

Answer 1

Option D.
`y=-4x^(2) -16x-12`

Explanation:

using a graphing tool

Graph and determine the vertex in each case

we know that

If the equation has a maximum value at x=-2, then the x-coordinate of the vertex must be equal to -2 and the parabola open downward

case A)
`y=-x^(2) -20x-16`

The vertex is the point
`(-10,84)`

case B)
`y=-x^(2) -16x-12`

The vertex is the point
`(-8,52)`

case C)
`y=-4x^(2) -20x-16`

The vertex is the point
`(-2.5,9)`

case D)
`y=-4x^(2) -16x-12`

The vertex is the point
`(-2,4)` -------> is the answer

see the attached figure