document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=117475>Question 117475</A>: <I><SPAN STYLE=\"word-break: break-all;\"> two vertical angles are supplementary. find the measure of each angle. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #86010 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=86010\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are two things you know about the vertical angles. The first thing is that this problem <BR>\n" );
document.write( "tells you they are supplementary. That means that the measures of the two angles add up to be<BR>\n" );
document.write( "180 degrees. Let mA represent the measure of vertical angle A and let mB represent the measure<BR>\n" );
document.write( "of vertical angle B. Since, according to the problem, the two angles are supplementary,<BR>\n" );
document.write( "you can write the supplementary angle equation:<BR>\n" );
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document.write( "mA + mB = 180<BR>\n" );
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document.write( "The other thing you can tell from geometry is that a pair of vertical angles will have equal<BR>\n" );
document.write( "measures. For this case, since A and B are vertical angles we can say that mA = mB.<BR>\n" );
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document.write( "You can return to the supplementary angle equation:<BR>\n" );
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document.write( "mA + mB = 180<BR>\n" );
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document.write( "and substitute mA for mB since the two are equal. After this substitution the supplementary<BR>\n" );
document.write( "angle equation becomes:<BR>\n" );
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document.write( "mA + mA = 180<BR>\n" );
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document.write( "The two terms on the left side add together to give:<BR>\n" );
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document.write( "2*mA = 180<BR>\n" );
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document.write( "To solve for mA, divide both sides by 2 to give:<BR>\n" );
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document.write( "mA = 180/2 = 90 degrees<BR>\n" );
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document.write( "and since mA = mB you know that the two vertical angles in this problem both have measures<BR>\n" );
document.write( "of 90 degrees.<BR>\n" );
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document.write( "Hope this helps you to understand the problem and how it can be solved. If you need assistance<BR>\n" );
document.write( "with understanding vertical angles and what they are, you can go to Wikipedia (the online<BR>\n" );
document.write( "encyclopedia) and look up \"vertical angles.\" That source has a description and drawing that<BR>\n" );
document.write( "shows vertical angles.<BR>\n" );
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