WEBVTT

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Here is the problem: (negative 5x plus 2)(4x plus 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.

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Combine like terms and order by degree.

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Read off the key features. degree 2, leading coefficient negative 20, constant term 10.

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So the answer is negative 20x squared minus 17x plus 10.

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In standard form the polynomial is negative 20x squared minus 17x plus 10 (degree 2, leading coefficient negative 20, constant term 10).

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Spot check at x equals 2: original and expanded form both give negative 104.