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Graph, rational zeros of a 3rd degree polynomial

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Description
f(x) = x3 + 4x2 - 25x - 28
  1. Factors of -28 (x0 term) go into the numerator; ±1,  ±2, ±4,  ±7,  ±14, ±28
  2. Factors of 1 (x3  term) go into the denominator: ±1
  3. Because the denominator is always ±1, the possible rational zeros are all integers
  4. f(-7) = f(-1) = f(4) = 0 All other x values produce f(x) ≠ 0
  5. Factored form of f(x) is: f(x) = (x+7)(x+1)(x-4)