document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=181206>Question 181206</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use indirect reasoning to explain why an obtuse triangle cannot have a right angle\r<BR>\n" );
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document.write( "This is a take home test question. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #135852 by </B><A HREF=/tutors/aboutme.mpl?userid=Mathtut><B>Mathtut(3670)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Mathtut><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=135852\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Identify the conjecture to be proven.<BR>\n" );
document.write( "Given: ABC is an obtuse , <BR>\n" );
document.write( "B is an obtuse angle;<BR>\n" );
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document.write( "Prove: ABC does not have a right angle.<BR>\n" );
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document.write( "2. Assume the opposite of the conclusion. Write this assumption.Assume ABC does have a right angle. Let A be a right angle.<BR>\n" );
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document.write( "3. Use direct reasoning to arrive at a contradiction. Possible answer: If A is a right angle, then measurement of angle B + angle C =90°. But angle B is  > 90°, since B is obtuse. So this is a contradiction.<BR>\n" );
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document.write( "4. What can you conclude? The assumption that ABC does have a right angle is false. Therefore ABC does not have a right angle. . </SPAN>\n" );
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