document.write( "Question 1129710: In Triange ABC, Angle A= 120 degrees and an exterior angle at C is 5x as large a Angle B. Find measurement of Angle B. \n" ); document.write( "
Algebra.Com's Answer #746289 by ankor@dixie-net.com(22740)\"\" \"About 
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In Triangle ABC, Angle A= 120 degrees
\n" ); document.write( "and an exterior angle at C is 5x as large a Angle B.
\n" ); document.write( "C = 180 - 5B
\n" ); document.write( "A + B + C = 180
\n" ); document.write( "Find measurement of Angle B.
\n" ); document.write( "Replace C with (180-5B)
\n" ); document.write( "120 + B + (180-5B) = 180
\n" ); document.write( "B + 180 - 5B = 180 - 120
\n" ); document.write( "B + 180 - 5B = 60
\n" ); document.write( "B - 5B = 60 - 180
\n" ); document.write( "-4B = -120
\n" ); document.write( "B = -120/-4
\n" ); document.write( "B = +30 degrees
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check this, find C
\n" ); document.write( "C = 180 - 5(30)
\n" ); document.write( "C = 180 - 150
\n" ); document.write( "C = 30 degrees also
\n" ); document.write( "120 + 30 + 30 = 180 \n" ); document.write( "
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