document.write( "Question 408312: how do I solve by addition. the second equation of the system has me stumped. How do I elimated one? \r
\n" ); document.write( "\n" ); document.write( "5x-7y=2
\n" ); document.write( "3x=4y \n" ); document.write( "
Algebra.Com's Answer #287708 by algebrahouse.com(1659)\"\" \"About 
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\"how do I solve by addition. the second equation of the system has me stumped. How do I elimate one?\" \r
\n" ); document.write( "\n" ); document.write( "5x - 7y = 2
\n" ); document.write( "3x = 4y-------->3x - 4y = 0 {subtracted 4y from both sides in 2nd equation}\r
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\n" ); document.write( "\n" ); document.write( "5x - 7y = 2-------> -15x + 21y = -6 {multiplied top equation by -3}
\n" ); document.write( "3x - 4y = 0-------> 15x - 20y = 0 {multiplied bottom equation by 5}\r
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\n" ); document.write( "\n" ); document.write( "-15x + 21y = -6
\n" ); document.write( "15x - 20y = 0
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\n" ); document.write( "y = -6 {added two new equations together and eliminated x}\r
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\n" ); document.write( "\n" ); document.write( "5x - 7y = 2 {top original equation}
\n" ); document.write( "5x - 7(-6) = 2 {substituted -6, in for y, into top original equation}
\n" ); document.write( "5x + 42 = 2 {multiplied -7 by -6}
\n" ); document.write( "5x = -40 {subtracted 42 from both sides}
\n" ); document.write( "x = -8 {divided both sides by 5}\r
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\n" ); document.write( "\n" ); document.write( "x = -8 and y = -6
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