document.write( "Question 1162499: Four angles of a pentagon are equal and the fifth is 60°. Find the equal angles and show that two sides of the pentagon are parallel. \n" ); document.write( "
Algebra.Com's Answer #786324 by Edwin McCravy(20056)\"\" \"About 
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document.write( "The sum of the interior angles of a pentagon have sum\r\n" );
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document.write( "(n-2)∙180° = (5-2)∙180° = 3∙180° = 540°.\r\n" );
document.write( "One of the interior angles is 60°\r\n" );
document.write( "So the other 4 interior angles have sum 540°-60° = 480°\r\n" );
document.write( "Since the other 4 angles are equal, they measure 480°÷4 = 120° each.\r\n" );
document.write( "The figure looks like this:\r\n" );
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document.write( "AB ∥ ED because m∠A + m∠E = 60° + 120° = 180° \r\n" );
document.write( "(if angles on the same side of two lines AB, ED, are supplementary when AB\r\n" );
document.write( "and ED are cut by the transversal AE, then the two lines are parallel. \r\n" );
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document.write( "AE ∥ BC because m∠A + m∠B = 60° + 120° = 180° \r\n" );
document.write( "(if angles on the same side of two lines AE, BC are supplementary when AE\r\n" );
document.write( "and BC are cut by the transversal AB, then the two lines are parallel.\r\n" );
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document.write( "Edwin
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