document.write( "Question 257488: 3/7x+5/9y=27 and 1/9x+2/7y=7 \n" ); document.write( "

Algebra.Com's Answer #189414 by stanbon(75887) $\"\"$ $\"About$

You can put this solution on YOUR website!
(3/7)x+(5/9)y=27
\n" ); document.write( "(1/9)x+(2/7)y=7
\n" ); document.write( "----------
\n" ); document.write( "Multiply thru the 1st by 63 and the 2nd by 63 to get:
\n" ); document.write( "-------
\n" ); document.write( "9*3x + 7*5y = 63*27
\n" ); document.write( "7*x + 9*2y = 63*7
\n" ); document.write( "---------------------------
\n" ); document.write( "27x + 35y = 63*27
\n" ); document.write( "7x + 18y = 63*7
\n" ); document.write( "-----------------------
\n" ); document.write( "Multiply the 1st by 7 and the 2nd by 27 to get:
\n" ); document.write( "7*27x + 7*35y = 7*63*27
\n" ); document.write( "27*7x + 27*18y = 27*63*7
\n" ); document.write( "-------------------------------
\n" ); document.write( "Subtract the 1st from the 2nd and solve for \"y\":
\n" ); document.write( "45y = 0
\n" ); document.write( "y = 0
\n" ); document.write( "------
\n" ); document.write( "Substitute into 7x + 18y = 7*63 to solve for \"x\":
\n" ); document.write( "7x = 7*63-0
\n" ); document.write( "x = 63
\n" ); document.write( "==============\r
\n" ); document.write( "\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "

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