document.write( "Question 732070: If AB = 10, BC = 9, and CA = 11, name the largest angle of ∆ABC. \n" ); document.write( "
Algebra.Com's Answer #447489 by Edwin McCravy(20056)\"\" \"About 
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document.write( "The largest side is opposite the largest angle.\r\n" );
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document.write( "The largest side is AC which is 11.\r\n" );
document.write( "The angle opposite AC is ∠B (which you may give as ∠ABC or as ∠CBA)\r\n" );
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document.write( "That may be all you are asked to find. But in case you have\r\n" );
document.write( "studied the law of cosines, I will continue to find the measure of\r\n" );
document.write( "∠B just in case:\r\n" );
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document.write( "To find the measure of ∠B we use the law of cosines:\r\n" );
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document.write( "cos(∠B) = \"%28a%5E2%2Bc%5E2-b%5E2%29%2F%282ac%29\"\r\n" );
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document.write( "cos(∠B) = \"%289%5E2%2B10%5E2-11%5E2%29%2F%282%2A9%2A10%29\"\r\n" );
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document.write( "cos(∠B) = \"%2881%2B100-121%29%2F180\" \r\n" );
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document.write( "cos(∠B) = \"60%2F180\"\r\n" );
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document.write( "cos(∠B) = \"1%2F3\" \r\n" );
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document.write( "Use the inverse cosine feature of your calculator:\r\n" );
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document.write( "m∠B = 70.52877937°\r\n" );
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document.write( "Edwin
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