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Identify the vertex, the axis of symmetry, maximum or minimum value, and range of the parabola y = -x² - x.

A) Vertex: (0, 0); Axis of Symmetry: x = 0; Minimum Value: 0; Range: y ≤ 0
B) Vertex: (0, -1/4); Axis of Symmetry: x = 0; Maximum Value: -1/4; Range: y ≥ -1/4
C) Vertex: (0, 0); Axis of Symmetry: x = 0; Maximum Value: 0; Range: y ≥ 0
D) Vertex: (0, -1); Axis of Symmetry: x = 0; Minimum Value: -1; Range: y ≤ -1

User Kris Boyd
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1 Answer

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Final answer:

None of the provided options correctly identify the vertex, axis of symmetry, maximum value, and range of the parabola y = -x² - x. The vertex is (-1/2, 1/4), the axis of symmetry is x = -1/2, the maximum value is 1/4, and the range is y ≤ 1/4.

Step-by-step explanation:

To identify the vertex, axis of symmetry, the maximum or minimum value, and the range of the parabola y = -x² - x, we first complete the square to find the vertex form of the equation. The given equation can be rewritten as y = -(x² + x + 1/4 - 1/4). Completing the square gives us y = -(x + 1/2)² + 1/4. The vertex form of the equation is y = a(x - h)² + k, where (h, k) is the vertex of the parabola. Comparing our completed square form, we get that the vertex is (-1/2, 1/4).

The axis of symmetry is the vertical line that passes through the vertex, hence it is x = -1/2. Since a = -1 in our equation and it is negative, the parabola opens downwards, indicating a maximum value, which is the y-coordinate of the vertex, 1/4. Lastly, the range of a downward-opening parabola is all real numbers less than or equal to its maximum value, which in this case is y ≤ 1/4.

Therefore, the correct statement from the given options would be none of them, because the correct vertex is (-1/2, 1/4), the axis of symmetry is x = -1/2, the maximum value is 1/4, and the range is y ≤ 1/4, which is not listed in any of the choices.

User Brian Nickel
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