document.write( "Question 252942: if 2y x 4x + 40 = 180 then what is the value of 2x + y ... thanks \n" ); document.write( "
Algebra.Com's Answer #185103 by drk(1908)\"\" \"About 
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We have the original equation as
\n" ); document.write( "(i) 2y x 4x + 40 = 180
\n" ); document.write( "subtract 40 to get
\n" ); document.write( "8xy = 140
\n" ); document.write( "(ii) xy = 17.5 = 35/2
\n" ); document.write( "(iii) 2x = 35y
\n" ); document.write( "(iv) 4x = 70y
\n" ); document.write( "substituting back into (i) and subtracting 40, we get
\n" ); document.write( "(v) 2y*70y = 140
\n" ); document.write( "(vi) 140y^2 = 140.
\n" ); document.write( "Y = +-1.
\n" ); document.write( "If y = 1, then x = 17.5
\n" ); document.write( "If y = -1, then x = -17.5
\n" ); document.write( "They both work in the original equation.
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