Answer: Choice B 6x^3-4x^2-8x-16
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Work Shown:
(3x^2+ 4x+4)(2x-4)
(2x-4)(3x^2+4x+4)
y(3x^2+4x+4) ...... let y = 2x-4
y(3x^2)+y(4x)+y(4) .... distribute
3x^2(y) + 4x(y) + 4(y)
3x^2(2x-4) + 4x(2x-4) + 4(2x-4) .... replace y with 2x-4
3x^2*2x+3x^2(-4)+4x(2x)+4x(-4)+4(2x)+4(-4) .... distribute
6x^3-12x^2+8x^2-16x+8x-16
6x^3-4x^2-8x-16
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Below is a diagram which might help you keep track of all the terms
Each cell is the result of multiplying the outer red and green terms. Example: Row 1, column 2 has 2x times 4x = 8x^2 (due to the 2x and 4x outside)
