document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=370056>Question 370056</A>: <I><SPAN STYLE=\"word-break: break-all;\"> prove line AC is parallel to line BD if line AB is the diameter of circle O and lines AC BD are the tangents. I need to know how to show the statement and the reason of how you are proving it please! i really need to learn </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #263713 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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/cgi-bin/show-face.mpl?user=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=263713\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing%28300%2C300%2C-10%2C10%2C-10%2C10%2Ccircle%280%2C0%2C5%29%2Ccircle%280%2C0%2C0.3%29%2Cline%280%2C-5%2C0%2C5%29%2Cline%28-10%2C5%2C10%2C5%29%2Cline%28-10%2C-5%2C10%2C-5%29%2Ccircle%288%2C5%2C0.2%29%2Ccircle%28-8%2C-5%2C0.2%29%2Clocate%288%2C5%2CC%29%2Clocate%28-9%2C-5%2CD%29%2Clocate%280%2C6%2CA%29%2Clocate%280%2C-5%2CB%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Since AC is a tangent, then the angle between AC and AB is 90 degrees. <BR>\n" );
document.write( "Same for the angle between BD and AB. <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=CAB=ABD=90 ALIGN=MIDDLE  ALT=\"CAB=ABD=90\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "They are alternate interior angles and since they are equal, AC is parallel to BD.  </SPAN>\n" );
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