document.write( "Question 717676: find the solution to each system by the substitution method 3x-5y=7 x-4y= -7 \n" ); document.write( "
Algebra.Com's Answer #440413 by checkley79(3341)\"\" \"About 
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3x-5y=7
\n" ); document.write( "x-4y= -7
\n" ); document.write( "x=4y-7 replace x with (4y-7) in the first equation & solve for y.
\n" ); document.write( "3(4y-7)-5y=7
\n" ); document.write( "12y-21-5y=7
\n" ); document.write( "7y=7+21
\n" ); document.write( "7y=28
\n" ); document.write( "y=28/7
\n" ); document.write( "y=4 ans.
\n" ); document.write( "x=4*4-7
\n" ); document.write( "x=16-7
\n" ); document.write( "x=9 ans.
\n" ); document.write( "Proof:
\n" ); document.write( "3*9-5*4=7
\n" ); document.write( "27-20=7
\n" ); document.write( "7=7
\n" ); document.write( "
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