document.write( "Question 124877This question is from textbook algebra I
\n" ); document.write( ": y=4x+11
\n" ); document.write( "-6x+8y=36\r
\n" ); document.write( "\n" ); document.write( "solving systems by substitution ??????? Help please !!!!!
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Algebra.Com's Answer #91525 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( "\"y=4x%2B11\"\r
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\n" ); document.write( "\n" ); document.write( "\"-6x%2B8%284x%2B11%29=36\" Plug in \"y=4x%2B11\" into the first equation. In other words, replace each \"y\" with \"4x%2B11\". 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( "\"-6x%2B32x%2B88=36\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"26x%2B88=36\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"26x=36-88\"Subtract 88 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"26x=-52\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-52%29%2F%2826%29\" Divide both sides by 26 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"x=-2\", we can plug this into \"y=4x%2B11\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=4%28-2%29%2B11\" Substitute \"-2\" for each \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=3\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-2\" and \"y=3\" 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+%2836%2B6x%29%2F8%2C+4x%2B11%29+\" Graph of \"-6x%2B8y=36\" (red) and \"y=4x%2B11\" (green)\r
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