document.write( "Question 739768: So I have a parallelogram (the top is A B the bottom is D C) and angle A says (3x+10)andlge B says (8x+5) angle D says 5y. angle C says nothing. I was wondering how I am supposed to solve this when andlge D and B have diff letter names and nothing matches A. Thanks:) \n" ); document.write( "
Algebra.Com's Answer #451336 by rothauserc(4718)\"\" \"About 
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we are given the parallelogram ABDC which means that AB is parallel to DC, furthermore opposite angles are equal which means\r
\n" ); document.write( "\n" ); document.write( "Angle A is equal to angle C and angle D is equal to angle B, also angles A and D add up to 180 degrees (supplementary angles) as well as angles B and C. So we have the following equations.\r
\n" ); document.write( "\n" ); document.write( "3x+10+5y=180
\n" ); document.write( "8x+5+angle C =180\r
\n" ); document.write( "\n" ); document.write( "but angle C = angle A so
\n" ); document.write( "8x+5+3x+10=180
\n" ); document.write( "11x+15=180
\n" ); document.write( "11x=165
\n" ); document.write( "x=15\r
\n" ); document.write( "\n" ); document.write( "substituting for x in equation one, we have\r
\n" ); document.write( "\n" ); document.write( "3*15 + 10 + 5y = 180
\n" ); document.write( "55 + 5y = 180
\n" ); document.write( "5y = 125
\n" ); document.write( "y = 25\r
\n" ); document.write( "\n" ); document.write( "so x = 15 and y = 25\r
\n" ); document.write( "\n" ); document.write( "that means angle A = 3 * 15 + 10 = 55, angel B = 8 * 15 + 5 = 125
\n" ); document.write( "angle D = 5 * 25 = 125 and angle C = angle A =55
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