Use a vertical format to find the product of the two polynomials. $\left( 3 x ^ { 2 } - 4 x - 4 \right) \left( 3 x ^ { 2 } - 4 x - 1 \right)$
A) $9 x ^ { 5 } - 24 x ^ { 3 } + x ^ { 2 } + 20 x + 4$
B) $9 x ^ { 4 } - 24 x ^ { 3 } + x ^ { 2 } + 20 x + 4$
C) $9 x ^ { 4 } - 24 x ^ { 3 } + 20 x + 4$
D) $9 x ^ { 4 } - 24 x ^ { 3 } + x ^ { 2 } + 4$
E) $9 x ^ { 4 } - 24 x ^ { 3 } + x ^ { 2 } + 20 x$

Question

Quizplus · Accepted Answer

3x^2 - 4x - 4
 x  3x^2 - 4x - 1
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    9x^4 - 12x^3 - 3x^2     ← (3x^2) * (-1) = -3x^4
-12x^3 + 16x^2 + 4x         ← (-4x) * (3x^2) + (-4x) * (-1)
-12x^2 + 16x + 4            ← (-4) * (3x^2) + (-4) * (-1)
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  9x^4 - 24x^3 + x^2 + 20x + 4

Use a Vertical Format to Find the Product of the Two