document.write( "Question 45638: substitution method\r
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Algebra.Com's Answer #30750 by mszlmb(115) $\"\"$ $\"About$

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y=13-3x
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document.write( "2x+9y=-8\r
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document.write( "the first equation tells you that y=13-3x.  so, replace y in the second equation with (13-3x).\r
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document.write( "2x+9(13-3x)=-8.   \r
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document.write( "simple enough.  Now solve.[distribute]\r
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document.write( "2x+117-27x=-8  -117, both sides
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document.write( "-25x=-125  divide by -25
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document.write( "x=5 \n" );
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