document.write( "Question 1209390: The sides of a triangle measure 4, 9, and 11. Is this a right triangle? If not then is it acute or obtuse? \n" ); document.write( "
Algebra.Com's Answer #848739 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "We use the Converse of the Pythagorean Theorem.
\n" ); document.write( "Here are the three possibilities:
  • If \"a%5E2%2Bb%5E2+=+c%5E2\" then it's a right triangle.
  • If \"a%5E2%2Bb%5E2+%3E+c%5E2\" then the triangle is acute.
  • If \"a%5E2%2Bb%5E2+%3C+c%5E2\" then the triangle is obtuse.
a,b,c are the sides of the triangle.
\n" ); document.write( "c is always the longest side. The a,b can be in any order.\r
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\n" ); document.write( "\n" ); document.write( "a = 4, b = 9, c = 11 are the three sides
\n" ); document.write( "\"a%5E2%2Bb%5E2+=+4%5E2%2B9%5E2+=+16%2B81+=+97\"
\n" ); document.write( "\"c%5E2+=+11%5E2+=+121\"\r
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\n" ); document.write( "\n" ); document.write( "In short,
\n" ); document.write( "\"a%5E2%2Bb%5E2+=+97\"
\n" ); document.write( "\"c%5E2+=+121\"\r
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\n" ); document.write( "\n" ); document.write( "The results 97 and 121 aren't equal, so the \"a%5E2%2Bb%5E2+=+c%5E2\" case is false.
\n" ); document.write( "This is not a right triangle.
\n" ); document.write( "The result of \"a%5E2%2Bb%5E2\" is smaller than the result of \"c%5E2\" (since 97 < 121) so we conclude that \"a%5E2%2Bb%5E2+%3C+c%5E2\" is case.
\n" ); document.write( "The triangle is obtuse. \r
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\n" ); document.write( "\n" ); document.write( "You can confirm this using an online tool such as this one or you can use GeoGebra (the GeoGebra link may take a bit of time to load).
\n" ); document.write( "There are many other similar online tools. \r
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\n" ); document.write( "\n" ); document.write( "Answer: Obtuse
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