document.write( "Question 1076771: In triangle DEF:
\n" ); document.write( "if m < D = 2 (m < E + m < F) which term best describes triangle DEF?\r
\n" ); document.write( "\n" ); document.write( "A) Acute
\n" ); document.write( "B) Equiangular
\n" ); document.write( "C) Right
\n" ); document.write( "D) Obtuse\r
\n" ); document.write( "\n" ); document.write( "An explanation would be nice, thank you. \n" ); document.write( "
Algebra.Com's Answer #691403 by MathTherapy(10810)\"\" \"About 
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In triangle DEF:
\n" ); document.write( "if m < D = 2 (m < E + m < F) which term best describes triangle DEF?\r
\n" ); document.write( "\n" ); document.write( "A) Acute
\n" ); document.write( "B) Equiangular
\n" ); document.write( "C) Right
\n" ); document.write( "D) Obtuse\r
\n" ); document.write( "\n" ); document.write( "An explanation would be nice, thank you.
\n" ); document.write( "
Let m∠E be x, and m∠F, y
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document.write( "Then m∠D = 2(x + y), or 2x + 2y
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document.write( "Since the angles of a triangle sum to 180o, then we get:
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document.write( "∠D + ∠E + ∠F = 180
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document.write( "2x + 2y + x + y = 180
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document.write( "3x + 3y = 180
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document.write( "3(x + y) = 3(60) ------ Factoring out GCF, 3
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document.write( "x + y = 60
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document.write( "Since ∠E = x, and ∠F = y, then ∠s E and F sum to 60o.
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document.write( "Therefore, ∠D MUST be 120o (180 - 60), which makes the triangle OBTUSE (CHOICE D). \n" );
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