document.write( "Question 1193135: Find the measures (in degrees) of the remaining angles of trapezoid ABCD if AB ∥ DC and m∠A = 59° and m∠C = 121
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Algebra.Com's Answer #825141 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Let's sketch it and see:\r\n" );
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document.write( "Draw DE perpendicular to parallel bases AB and DC.\r\n" );
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document.write( "1. Now since triangle AEB is a right triangle, you can find m∠ADE.\r\n" );
document.write( "And you know that m∠EDC = 90o, now you can find the measure\r\n" );
document.write( "of the whole angle at D, namely m∠ADC, which could be called m∠D \r\n" );
document.write( "before we drew in DE.\r\n" );
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document.write( "2. Now that you have the measures of all but one of the interior angles, \r\n" );
document.write( "use the fact that the sum of the measures of the interior angles of\r\n" );
document.write( "any quadrilateral is 360o to find m∠B.\r\n" );
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document.write( "Edwin
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