How can I find the x-intercept of a cubic polynomial?

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Chocolaty
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I have to sketch the graph of this function:
f(x) = x^3 + 3x^2 - 9x +5

But how can I find the x-intercept (where y = 0) in this function?
 
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for cubic polynomials in order to find the x intercepts you need to look at hte integer factors of the constant (x^0) term
here look at the factors of 5 they are
+/-1,+/-5
so find f(1), f(-1), f(5), f(-5) and determine which one is zero
SUPPOSE (not necessarily true) f(1) = 0, then x = 1, and x-1 is a factor

thereafter long divide the polynomial by x-1 and then you can find more intercepts easily from the factored form.