document.write( "Question 424971: i need your help in solving this equation: using comparion method\r
\n" ); document.write( "\n" ); document.write( "y=2x-3
\n" ); document.write( "y=-1/2x+4\r
\n" ); document.write( "\n" ); document.write( "and this one using substitution method\r
\n" ); document.write( "\n" ); document.write( "x-2y=3
\n" ); document.write( "2x-3y=y\r
\n" ); document.write( "\n" ); document.write( "thank you so much, ana
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Algebra.Com's Answer #296086 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"y=2x-3\".....1...
\n" ); document.write( "\"y=-%281%2F2%29x%2B4\"....2\r
\n" ); document.write( "\n" ); document.write( "first multiply second equation by \"4\" then add 1 and 2\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-3\".....1...
\n" ); document.write( "\"4y=4%28-1%2F2%29x%2B4%2A4\"....2\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-3\".....1...
\n" ); document.write( "\"4y=cross%284%292%28-1%2Fcross%282%29%29x%2B16\"....2\r
\n" ); document.write( "\n" ); document.write( "\"y=2x-3\".....1...
\n" ); document.write( "\"4y=-2x%2B16\"....2
\n" ); document.write( "------------------------ now add them\r
\n" ); document.write( "\n" ); document.write( "\"y%2B4y=2x%2B%28-2x%29-3%2B16\"\r
\n" ); document.write( "\n" ); document.write( "\"5y=cross%282x%29%2Bcross%28%28-2x%29%29-3%2B16\"\r
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\n" ); document.write( "\n" ); document.write( "\"5y=13\"}\r
\n" ); document.write( "\n" ); document.write( "\"y=13%2F5\"\r
\n" ); document.write( "\n" ); document.write( "\"y=2.6\"....now find \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-3\".....1...\r
\n" ); document.write( "\n" ); document.write( "\"2.6%2B3=2x\"\r
\n" ); document.write( "\n" ); document.write( "\"5.6=2x\"\r
\n" ); document.write( "\n" ); document.write( "\"5.6%2F2=+x\"\r
\n" ); document.write( "\n" ); document.write( "\"2.8=+x\"\r
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\n" ); document.write( "\n" ); document.write( "check:\r
\n" ); document.write( "\n" ); document.write( "\"4y=-2x%2B16\"....2\r
\n" ); document.write( "\n" ); document.write( "\"4%2A2.6=-2%2A2.8%2B16\"\r
\n" ); document.write( "\n" ); document.write( "\"10.4+=+-5.6%2B16\"\r
\n" ); document.write( "\n" ); document.write( "\"10.4+=+10.4\"\r
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\n" ); document.write( "\n" ); document.write( "2.\r
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\n" ); document.write( "\n" ); document.write( "using substitution method\r
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Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
\n" ); document.write( " \"+system%28+%0D%0A++++1%5Cx+%2B+-2%5Cy+=+3%2C%0D%0A++++2%5Cx+%2B+-4%5Cy+=+0+%29%0D%0A++\"We'll use substitution. After moving -2*y to the right, we get:
\n" ); document.write( " \"1%2Ax+=+3+-+-2%2Ay\", or \"x+=+3%2F1+-+-2%2Ay%2F1\". Substitute that
\n" ); document.write( " into another equation:
\n" ); document.write( " \"2%2A%283%2F1+-+-2%2Ay%2F1%29+%2B+-4%5Cy+=+0\" and simplify: So, we know that y=6=0. Since \"x+=+3%2F1+-+-2%2Ay%2F1\", x=15.
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\n" ); document.write( " Answer: \"system%28+x=15%2C+y=6=0+%29\".
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