document.write( "Question 52885: Solve the system of equations: (hint: let (1/x)=t and (1/y)=u)\r
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document.write( "(2/x)+(1/y)=11
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document.write( "(3/x)-(5/y)=10 \n" );
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Algebra.Com's Answer #35267 by funmath(2933)![]() ![]() ![]() You can put this solution on YOUR website! (2/x)+(1/y)=11 \n" ); document.write( "(3/x)-(5/y)=10 \n" ); document.write( "---------------- \n" ); document.write( "2(1/x)+(1/y)=11 \n" ); document.write( "3(1/x)-5(1/y)=10 \n" ); document.write( "------------------ \n" ); document.write( "Let 1/x=t and 1/y=u \n" ); document.write( "2t+u=11 \n" ); document.write( "3t-5u=10 \n" ); document.write( "------------------- \n" ); document.write( "Solve the first equation for u, substitute it for u in the second equation and solve for t. \n" ); document.write( "2t+u=11 \n" ); document.write( "-2t+2t+u=-2t+11 \n" ); document.write( "u=-2t+11 \n" ); document.write( "3t-5(-2t+11)=10 \n" ); document.write( "3t+10t-55=10 \n" ); document.write( "13t-55=10 \n" ); document.write( "13t-55+55=10+55 \n" ); document.write( "13t=65 \n" ); document.write( "13t/13=65/13 \n" ); document.write( "t=5 \n" ); document.write( "---------------------------- \n" ); document.write( "Substitute that answer for t in the first equation and solve for u. \n" ); document.write( "2(5)+u=11 \n" ); document.write( "10+u=11 \n" ); document.write( "-10+10+u=11-10 \n" ); document.write( "u=1 \n" ); document.write( "----------------------------- \n" ); document.write( "Only we were supposed to find x and y not t and u, so let t=1/x and u=1/y and solve for x and y. \n" ); document.write( "t=5 becomes 1/x=5 \n" ); document.write( "x(1/x)=5x \n" ); document.write( "1=5x \n" ); document.write( "1/5=5x/5 \n" ); document.write( "1/5=x \n" ); document.write( "u=1 becomes 1/y=1 \n" ); document.write( "y(1/y)=1(y) \n" ); document.write( "1=y \n" ); document.write( "Therefore, our answer is (x,y)=(1/5,1) \n" ); document.write( " |