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K(x)=10-4x-x^2 where x∈r and x≥1 find vertex, range, x intercepts and y intercept

User EHayik
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1 Answer

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Final answer:

The vertex of the quadratic function K(x)=10-4x-x^2 is (-2, 14), the range is y≤14 for x≥1, the x-intercepts can be found by solving the equation set to zero, and the y-intercept is (0, 10).

Step-by-step explanation:

The function described is K(x) = 10 - 4x - x^2, which is a quadratic function, where x is restricted to the real numbers and x ≥1. To find the vertex, range, and intercepts, we need to analyze this quadratic function.

Vertex

The vertex form of a quadratic function is y = a(x - h)^2 + k, where (h, k) is the vertex of the parabola. For K(x), we complete the square to find its vertex form:

K(x) = -x^2 - 4x + 10
= -(x^2 + 4x - 4) + 10 + 4
= -(x + 2)^2 + 14

The vertex is at (-2, 14).

Range

Since the coefficient of the x^2 term is negative, the parabola opens downwards, making the vertex the maximum point. Therefore, the range is y ≤ 14, for x ≥ 1.

X-Intercepts

We find the x-intercepts by setting K(x) to zero and solving for x:

0 = 10 - 4x - x^2

Applying the quadratic formula, we get two x-intercepts, which are the solutions to the equation.

Y-Intercept

The y-intercept occurs when x = 0. Substituting 0 into K(x), we get:

K(0) = 10 - 4(0) - (0)^2 = 10

Thus, the y-intercept is (0, 10).

User Seif Sallam
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