Final answer:
To simplify the expression -16x + 3x^2 - 8x^2, we should combine like terms and write the terms in descending powers of x. There is no constant term in this expression. If x = -1, the value of the expression -5x^2 - 16x is 11.
Step-by-step explanation:
To simplify the expression -16x + 3x^2 - 8x^2, we should combine like terms. Adding the coefficients of x^2, we get -16x + 3x^2 - 8x^2 = -16x - 5x^2. Writing the terms in descending powers of x, we have -5x^2 - 16x.
The constant term is the term that does not contain any powers of x. In this expression, the constant term is 0 since there is no constant term.
If we substitute x = -1 into the expression -5x^2 - 16x, we get -5(-1)^2 - 16(-1) = -5 - (-16) = -5 + 16 = 11.
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