WEBVTT
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Expand two 𝑥 plus five all squared.
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Squaring a number is the same as multiplying it by itself.
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Therefore, to expand two 𝑥 plus five all squared, we must first rewrite it as two 𝑥 plus five multiplied by two 𝑥 plus five.
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In order to expand these two parentheses or brackets, we’ll use the FOIL method.
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We’ll firstly multiply the first terms.
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Then, we’ll multiply the outside terms, then the inside, and finally the last terms.
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Multiplying the first terms, two 𝑥 multiplied by two 𝑥 gives us four 𝑥 squared.
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Multiplying the outside terms, two 𝑥 multiplied by positive five gives us positive 10𝑥.
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In the same way, multiplying the inside terms, positive five and two 𝑥, also gives us positive 10𝑥.
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Finally, multiplying the last terms, positive five multiplied by positive five gives us positive 25.
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We can then simplify or group the middle terms positive 10𝑥 plus 10𝑥 is equal to positive 20𝑥.
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Therefore, our expansion is four 𝑥 squared plus 20𝑥 plus 25.
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This is an example of expanding a perfect square.