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What are the x-intercepts of the graph of the given function f(x)=3(x+7)(x-9) show your work

1 Answer

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Answer:

x intercepts = (9,0), (-7,0)

Explanation:

First lets expand the factored equation.

f(x) = 3(x + 7) (x - 9)

.... = 3x + 21 (x - 9)

....= 3x^2 - 27x - 21x - 189

....= 3x^2 - 6x - 189

lets make the quation equal to 0 and use the Factorization method to solve for x.

3x^2 - 6x - 189= 0

3(x^2 - 2x - 63) = 0

3(x - 9) (x + 7) = 0

x - 9 = 9 and x + 7 = -7

x = 9,

x = -7

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