document.write( "Question 202419: Solve the given system by use of substitution:\r
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Algebra.Com's Answer #152649 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"system%284x%2B5y=8%2C-6x%2By=56%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B5y=8\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"5y=8-4x\" Subtract \"4x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%288-4x%29%2F%285%29\" Divide both sides by \"5\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%284%2F5%29x%2B8%2F5\" Rearrange the terms and simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"-6x%2By=56\" Move onto the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-6x-%284%2F5%29x%2B8%2F5=56\" Now plug in \"y=-%284%2F5%29x%2B8%2F5\".\r
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\n" ); document.write( "\n" ); document.write( " Multiply EVERY term by the LCD \"5\" to clear any fractions.\r
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\n" ); document.write( "\n" ); document.write( "\"-30x-4x%2B8=280\" Multiply and simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"-34x%2B8=280\" Combine like terms on the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"-34x=280-8\" Subtract \"8\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-34x=272\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28272%29%2F%28-34%29\" Divide both sides by \"-34\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-8\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-8\", we can use this to find \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B5y=8\" Go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"4%28-8%29%2B5y=8\" Plug in \"x=-8\".\r
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\n" ); document.write( "\n" ); document.write( "\"-32%2B5y=8\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"5y=8%2B32\" Add \"32\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"5y=40\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2840%29%2F%285%29\" Divide both sides by \"5\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=8\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-8\" and \"y=8\".\r
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\n" ); document.write( "\n" ); document.write( "This means that the system is consistent and independent.\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"4x%2B5y=8\" (red) and \"-6x%2By=56\" (green)
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