document.write( "Question 499347: the second angle of a triangle measures 10 degrees more than the first angle. the third angle measures 30 degrees less than twice the second angle. what are the measures of the three angles? \n" ); document.write( "

Algebra.Com's Answer #337604 by oberobic(2304) $\"\"$ $\"About$

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a = first angle
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\n" ); document.write( "b = second angle
\n" ); document.write( "b = a+10 (given)
\n" ); document.write( "or
\n" ); document.write( "a = b-10
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\n" ); document.write( "c = third angle
\n" ); document.write( "c = 2b - 30
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\n" ); document.write( "a + b + c = 180 (because it's a triangle)
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\n" ); document.write( "substitute
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\n" ); document.write( "(b-10) + b + (2b-30) = 180
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\n" ); document.write( "b -10 +b +2b -30 = 180
\n" ); document.write( "4b -40 = 180
\n" ); document.write( "4b = 220
\n" ); document.write( "b = 55
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\n" ); document.write( "a = b-10
\n" ); document.write( "a = 45
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\n" ); document.write( "Therefore,
\n" ); document.write( "c = 180 - (55+45)
\n" ); document.write( "c = 80
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\n" ); document.write( "Check:
\n" ); document.write( "2b - 30 = 2(55) - 30
\n" ); document.write( " = 110 - 30
\n" ); document.write( " = 80
\n" ); document.write( "True.
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\n" ); document.write( "Answer:
\n" ); document.write( "The three angles are 45, 55, and 80 degrees.
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\n" ); document.write( "Done. \n" ); document.write( "

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