document.write( "Question 1129631: Two consecutive angles of a parallelogram are in the ratio 4:5.How many degrees are there in each angle of the parallelogram? \n" ); document.write( "
Algebra.Com's Answer #746209 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "by definition, the sum of the angles for each quadrilateral is \"360\"°
\n" ); document.write( "the sum of the \"two\" consecutive angles of a parallelogram have to be equal to \"180\" degrees\r
\n" ); document.write( "\n" ); document.write( "let \"x\" = one of the angles and let\"+y\" = the other angle.\r
\n" ); document.write( "\n" ); document.write( "\"x+%2B+y+=+180\"\r
\n" ); document.write( "\n" ); document.write( "the ratio of one of these angles to the other is \"4%2F5\"\r
\n" ); document.write( "\n" ); document.write( "this means that \"x%2Fy+=+4%2F5\"\r
\n" ); document.write( "\n" ); document.write( "solve for \"x\" to get \"x+=+%284%2F5%29+y\"\r
\n" ); document.write( "\n" ); document.write( "then \"x+%2B+y+=+180\" becomes
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\n" ); document.write( "\"%284%2F5%29+y+%2B+y+=+180\" ....solve for \"y\"\r
\n" ); document.write( "\n" ); document.write( "\"%284%2F5%29+y+%2B%285%2F5%29+y+=+180\"\r
\n" ); document.write( "\n" ); document.write( " \"%289%2F5%29+y+=+180\"\r
\n" ); document.write( "\n" ); document.write( "\"+y+=+180%2F%289%2F5%29\"\r
\n" ); document.write( "\n" ); document.write( "\"+y+=+%28180%2A5%29%2F9\"\r
\n" ); document.write( "\n" ); document.write( "\"+y+=+%28cross%28180%2920%2A5%29%2Fcross%289%29\"\r
\n" ); document.write( "\n" ); document.write( "\"+y+=+100\"\r
\n" ); document.write( "\n" ); document.write( "then, \"x+%2B+100+=+180\"=> \"x=80\"\r
\n" ); document.write( "\n" ); document.write( "the sum of two consecutive angles is equal to \"100+%2B+80+=+180\"
\n" ); document.write( "this confirms the solution is correct.\r
\n" ); document.write( "\n" ); document.write( "check the ratio:\r
\n" ); document.write( "\n" ); document.write( "\"80%2F100=4%2F5\"
\n" ); document.write( "\"8%2F10=4%2F5\"
\n" ); document.write( "\"4%2F5=4%2F5\"=> proves that angles of a parallelogram are in the ratio \"4%3A5\"\r
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