WEBVTT

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Here is the problem: (negative 5x plus 1)(negative 4x minus 5).

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Expand and simplify the polynomial into standard form.

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Distribute every product and power. Multiply each term of one factor by each term of the other; expand powers by repeated multiplication.

4
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Combine like terms and order by degree.

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Read off the key features. degree 2, leading coefficient 20, constant term negative 5.

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So the answer is 20x squared plus 21x minus 5.

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In standard form the polynomial is 20x squared plus 21x minus 5 (degree 2, leading coefficient 20, constant term negative 5).

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Spot check at x equals 2: original and expanded form both give 117.