document.write( "Question 708287: Which one of the following could represent two of the three angles of an acute triangle?
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\n" ); document.write( "4 degrees and 100 degrees
\n" ); document.write( "60 degrees and 10 degrees
\n" ); document.write( "31 degrees 59 degrees \n" ); document.write( "
Algebra.Com's Answer #436047 by Edwin Parker(36)\"\" \"About 
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document.write( "Any angle less than 90° is an acute angle.\r\n" );
document.write( "Every triangle has two acute angles.\r\n" );
document.write( "But some triangles have all three angles acute.\r\n" );
document.write( "When all three angles of a triangle are acute, we call\r\n" );
document.write( "it an \"acute triangle\".\r\n" );
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document.write( "Since we know that the sum of the three angles of\r\n" );
document.write( "every triangle is 180°, then if we know two angles, we\r\n" );
document.write( "can find the third angle by adding those two and subtracting\r\n" );
document.write( "from 180°  \r\n" );
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\n" ); document.write( "28 degrees and 66 degrees
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document.write( "Those two angles are acute because they are both less than 90°.\r\n" );
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document.write( "We add them 28° + 66° and get 94°.\r\n" );
document.write( "Now we subtract 180° - 94° and get 86°.\r\n" );
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document.write( "So therefore all thre angles of that triangle are less than\r\n" );
document.write( "90°, so we know that it IS an ACUTE triangle.\r\n" );
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\n" ); document.write( "4 degrees and 100 degrees
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document.write( "We know immediately that this is not an acute triangle because\r\n" );
document.write( "100° is NOT an acute angle, because it is greater than 90°.\r\n" );
document.write( "Angles greater than 90° are called \"obtuse\", and so this is\r\n" );
document.write( "NOT an acute triangle.  It is an obtuse triangle.\r\n" );
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\n" ); document.write( "60 degrees and 10 degrees
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document.write( "Those two angles are acute because they are both less than 90°.\r\n" );
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document.write( "We add them 60° + 10° and get 70°.\r\n" );
document.write( "Now we subtract 180° - 70° and get 110°.\r\n" );
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document.write( "But 110° is greater than 90°, therefore this is NOT an\r\n" );
document.write( "acute triangle.  It's an obtuse triangle.\r\n" );
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\n" ); document.write( "31 degrees 59 degrees
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document.write( "Those two angles are acute because they are both less than 90°.\r\n" );
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document.write( "We add them 31° + 59° and get 90°.\r\n" );
document.write( "Now we subtract 180° - 90° and get 90°.\r\n" );
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document.write( "But 90° is NOT greater than 90°, therefore this is NOT an\r\n" );
document.write( "acute triangle.  It's a RIGHT triangle, because it has a\r\n" );
document.write( "90° angle.\r\n" );
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document.write( "Edwin
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