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Write an equation for a polynomial function whose graph intercepts the horizontal axis at -7, 8, 15.

A. f(x) = (x + 7)(x - 8)(x - 15)
B. f(x) = (x - 7)(x + 8)(x + 15)
C. f(x) = (x - 7)(x - 8)(x - 15)
D. f(x) = (x + 7)(x + 8)(x + 15)

User Apinho
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1 Answer

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Final answer:

The correct equation for a polynomial function that intercepts the horizontal axis at -7, 8, 15 is f(x) = (x + 7)(x - 8)(x - 15).

Step-by-step explanation:

The question asks for the equation of a polynomial function whose graph intercepts the horizontal axis at -7, 8, 15. To find the polynomial equation, we need to transform the x-intercepts into factors of the polynomial. For the graph of a polynomial to intercept the horizontal axis at a certain x-value, that x-value must be a root of the polynomial, meaning that the polynomial can be factored to have a term of the form (x - r) where r is a root. Therefore, if we have roots at -7, 8, and 15, the factors of the polynomial are (x + 7), (x - 8), and (x - 15), respectively. Multiplying these factors gives us the polynomial in expanded form.

The correct equation for a polynomial function that meets the given conditions is:

f(x) = (x + 7)(x - 8)(x - 15)

User Kazutaka
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