document.write( "Question 121018: Solve each system by the substitution method. determine whether the equstions are independent, dependent, or inconsistent.\r
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\n" ); document.write( "\n" ); document.write( "x=2y-7
\n" ); document.write( "3x+2y=-5
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Algebra.Com's Answer #88811 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Start with the given system\r
\n" ); document.write( "\n" ); document.write( "\"3x%2B2y=-5\"
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\n" ); document.write( "\n" ); document.write( "\"3%282y-7%29%2B2y=-5\" Plug in \"x=2y-7\" into the first equation. In other words, replace each \"x\" with \"2y-7\". Notice we've eliminated the \"x\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"6y-21%2B2y=-5\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"8y-21=-5\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"8y=-5%2B21\"Add 21 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"8y=16\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2816%29%2F%288%29\" Divide both sides by 8 to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"y=2\", we can plug this into \"x=2y-7\" to find \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=2%282%29-7\" Substitute \"2\" for each \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-3\" and \"y=2\" which also looks like \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the two equations, we can see that their intersection is at . So this verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-5%2C+5%2C+-5%2C+5%2C+%28-5-3x%29%2F2%2C+%28x%2B7%29%2F2%29+\" Graph of \"3x%2B2y=-5\" (red) and \"x=2y-7\" (green)\r
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