document.write( "Question 255613: A triangle has sides which are 9, 40, and 41 millimeters long. How could you determine if this triangle is or is not a right triangle? \n" ); document.write( "
Algebra.Com's Answer #187824 by drk(1908)\"\" \"About 
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We have a thing called the triangle inverse theorem. This has three parts:
\n" ); document.write( "If \"a%5E2+%2B+b%5E2+%3C+c%5E2\" then triangle is obtuse
\n" ); document.write( "If \"a%5E2+%2B+b%5E2+=+c%5E2\" then triangle is right
\n" ); document.write( "If \"a%5E2+%2B+b%5E2+%3E+c%5E2\" then triangle is acute
\n" ); document.write( "We also have the triangle inequality statement which says
\n" ); document.write( "\"a+%2B+b+%3E+c\"
\n" ); document.write( "step 1 - apply our numbers to the inequality and we get
\n" ); document.write( "9+40 > 41.
\n" ); document.write( "So, we have a triangle. Now we put the numbers into the inverse theorem and get
\n" ); document.write( "\"9%5E2+%2B+%2840%5E2%29+__+41%5E2\"
\n" ); document.write( "\"81+%2B+1600+__+1681\"
\n" ); document.write( "\"1681+=+1681\"
\n" ); document.write( "This is a right triangle.
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