(3x2 + 5x + 9)(6x - 8)
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Step-by-step explanation:
(3x2 + 5x + 9)(6x - 8)
6x(3x2 + 5x + 9) - 8(3x2 + 5x + 9)
18x^3 + 30x^2 + 54 - 24x^2 - 40x - 72
18x^3 + 54x^2 -72 - 40x + 54
18x^3 + 54x^2 - 40x - 18