document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=86191>Question 86191</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Theorem: The bisector of the vertex angle of an isosceles triangle is perpendicular to the base of the triangle.\r<BR>\n" );
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document.write( "Given:?<BR>\n" );
document.write( "To prove:?<BR>\n" );
document.write( "Analysis:?\r<BR>\n" );
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document.write( "I have to proof by writing a statement and the reason for that statement.\r<BR>\n" );
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document.write( "Thank you<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #62305 by </B><A HREF=/tutors/aboutme.mpl?userid=scianci><B>scianci(186)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scianci><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=62305\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Given: Isosceles triangle ABC with AB congruent to AC [you draw]<BR>\n" );
document.write( "       AD bisects angle BAC [you draw ; endpoint D on base BC]\r<BR>\n" );
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document.write( "Prove: AD perpendicular to BC\r<BR>\n" );
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document.write( "1. Isosceles triangle ABC with AB congruent to AC     1. given<BR>\n" );
document.write( "   AD bisects angle BAC<BR>\n" );
document.write( "2. angle BAD congruent to angle CAD                  2. def. of angle bisector<BR>\n" );
document.write( "3. AD congruent to AD                                3. reflexive property<BR>\n" );
document.write( "4. triangle BAD congruent to triangle CAD            4. SAS<BR>\n" );
document.write( "5. angle BDA congruent to angle CDA                  5. CPCTC<BR>\n" );
document.write( "6. m angle BDA + m angle CDA = 180                   6. linear pair postulate<BR>\n" );
document.write( "7. m angle BDA = m angle CDA                         7. def. congruent angles<BR>\n" );
document.write( "8. m angle BDA + m angle BDA = 180                   8. substitution<BR>\n" );
document.write( "9.  2*m angle BDA = 180                              9. substitution<BR>\n" );
document.write( "10. m angle BDA = 90                                 10. division prop.<BR>\n" );
document.write( "11. AD perpendicular to BC                           11. def. perpendicular </SPAN>\n" );
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