document.write( "Question 154087: Explain the following in your own words: (a + b)2 a2 + b2. Give a numerical example to illustrate this. \n" ); document.write( "
Algebra.Com's Answer #113408 by jim_thompson5910(35256)\"\" \"About 
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Algebraic Explanation:\r
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\n" ); document.write( "\n" ); document.write( "\"%28a%2Bb%29%5E2=a%5E2+%2B+b%5E2\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2%2B2ab%2Bb%5E2=a%5E2+%2B+b%5E2\" FOIL the left side
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\n" ); document.write( "\n" ); document.write( "\"2ab=a%5E2+%2B+b%5E2-a%5E2-b%5E2\" Subtract \"a%5E2\" from both sides. Subtract \"b%5E2\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2ab=0\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "Case 1: Solving for \"a\"\r
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\n" ); document.write( "\n" ); document.write( "\"a=0%2F%282b%29\" Divide both sides by \"2b\"\r
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\n" ); document.write( "\n" ); document.write( "\"a=0\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Or...\r
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\n" ); document.write( "\n" ); document.write( "Case 2: Solving for \"b\"\r
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\n" ); document.write( "\n" ); document.write( "\"b=0%2F%282a%29\" Divide both sides by \"2b\"\r
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\n" ); document.write( "\n" ); document.write( "\"b=0\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So \"%28a%2Bb%29%5E2=a%5E2+%2B+b%5E2\" is true only if \"a\" or \"b\" is 0 (or both are zero). Otherwise, the equation is false. So in general \"%28a%2Bb%29%5E2+%3C%3E+a%5E2+%2B+b%5E2\" \r
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\n" ); document.write( "\n" ); document.write( "Numerical Example:\r
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\n" ); document.write( "\n" ); document.write( "\"%28a%2Bb%29%5E2=a%5E2+%2B+b%5E2\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"%285%2B4%29%5E2=5%5E2%2B4%5E2\" Plug in a=5 and b=4 (any two numbers will do as long as they are both not equal to zero)\r
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\n" ); document.write( "\n" ); document.write( "\"%289%29%5E2=5%5E2%2B4%5E2\" Add\r
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\n" ); document.write( "\n" ); document.write( "\"81=25%2B16\" Square each term\r
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\n" ); document.write( "\n" ); document.write( "\"81=41\" Add\r
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\n" ); document.write( "\n" ); document.write( "Since \"81=41\" is not true, this means that we've just shown that \"%28a%2Bb%29%5E2=a%5E2+%2B+b%5E2\" is not true for all values of \"a\" and \"b\". \r
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\n" ); document.write( "\n" ); document.write( "So once again, in general \"%28a%2Bb%29%5E2+%3C%3E+a%5E2+%2B+b%5E2\"
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