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5 votes
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y = -x2 - 6x - 7
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what is the axis of symmetry and vertex?

User Metis
by
5.2k points

1 Answer

5 votes

Answer:

x = 3, (3, -34)

Explanation:

Please write this as y = -x^2 - 6x - 7. Here we use " ^ " to indicate exponentiation. The coefficients of this quadratic equation are a = -1, b = -6 and c = -7.

-b

Using the formula for the axis of symmetry, x = --------

2a

-(-6)

we find that this axis in this case is x = ---------- = 6/2 = 3.

2(-1)

The axis of symmetry is x = 3.

We use this x value to determine the y-value at the vertex:

y = -(3)^2 - 6(3) - 7 = -9 - 18 - 7 = -34

The vertex is (3, -34).

User Adam Wenger
by
5.4k points