Answer:
2x^2 -4x -16
Explanation:
The product of two polynomials is the sum of the products of every term of one with every term of the other. Like terms are combined. In standard form, the highest degree term is listed first, and other terms are listed in order of decreasing degree.
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The attached table shows the term-by-term products. The linear terms 4x and -8x are "like" terms and can be combined to (4-8)x = -4x. The standard form product is also shown in the attachment.
(2x +4)(x -4) = 2x^2 -4x -16