WEBVTT

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Here is the problem: (5x plus 3)(5x plus 1).

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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 25, constant term 3.

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So the answer is 25x squared plus 20x plus 3.

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In standard form the polynomial is 25x squared plus 20x plus 3 (degree 2, leading coefficient 25, constant term 3).

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Spot check at x equals 2: original and expanded form both give 143.