Algebra

Every item in the first term is multiplied with every item in the second term.    

Pick out the items that, when multiplied, result in an "x" coefficient product.    

(x3 + x2 + x + 1) • (x4 – 8x3 + 17x2 – 23x + 14)     gives you + 14x    

(x3 + x2 + x + 1) • (x4 – 8x3 + 17x2 – 23x + 14)     gives you – 23x    

add them together for the final value                                     – 9x    

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