document.write( "Question 131039: Solve the system of equations by the substitution method.\r
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\n" ); document.write( "(Type an ordered pair. Type integers or simplified fractions. Type N if there is no solution. Type I if there are infinitely many solutions.)
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Algebra.Com's Answer #95657 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system\r
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\n" ); document.write( "\n" ); document.write( "\"9x%2B10=6x%2B8\" Plug in \"y=9x%2B10\" into the first equation. In other words, replace each \"y\" with \"9x%2B10\". Notice we've eliminated the \"y\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"9x=6x%2B8-10\" Subtract 10 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"9x-6x=8-10\" Subtract 6x from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"3x=8-10\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"3x=-2\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-2%29%2F%283%29\" Divide both sides by 3 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"x=-2%2F3\", we can plug this into \"y=9x%2B10\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=9%28-2%2F3%29%2B10\" Substitute \"-2%2F3\" for each \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=4\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-2%2F3\" and \"y=4\" 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+6x%2B8%2C+9x%2B10%29+\" Graph of \"y=6x%2B8\" (red) and \"y=9x%2B10\" (green)\r
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