document.write( "Question 1036433: The diagonals of a parallelogram have lengths of 12cm and 18cm and the angle between them is 72degree.
\n" ); document.write( "Find the lengths of the sides of the parallelogram.\r
\n" ); document.write( "\n" ); document.write( "I have 1 side which is 9.1 by using the cosine rule but the second side , i do not know how to do. \n" ); document.write( "
Algebra.Com's Answer #651092 by Theo(13342)\"\" \"About 
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i duplicated what i think you did and i got one of the sides of the parallelogram is equal to 9.144734256.\r
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\n" ); document.write( "\n" ); document.write( "i used the 72 degree angle.\r
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\n" ); document.write( "\n" ); document.write( "since the intersection of the diagonals leads to congruent vertical angles and supplementary adjacent angles, you should be able to do the same for the longer side.\r
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\n" ); document.write( "\n" ); document.write( "the same formula can be used, only this time the angle is 108 degrees rather than 72.\r
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\n" ); document.write( "\n" ); document.write( "you would get c^2 = 6^2 + 9^2 - 2*6*9*cos(108) which should result in c = 12.26270098 which would be the length of the other side.\r
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\n" ); document.write( "\n" ); document.write( "that's my thinking, anyway.\r
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