document.write( "Question 202424: Solve the given system by use of elimination:\r
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Algebra.Com's Answer #152654 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"4x-9y=10.5\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"10%284x%29-10%289y%29=10%2810.5%29\" Multiply EVERY term by 10 to make every value a whole number.\r
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\n" ); document.write( "\n" ); document.write( "\"40x-90y=105\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"7y-2x=-6.5\" Move onto the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2B7y=-6.5\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "\"10%28-2x%29%2B10%287y%29=10%28-6.5%29\" Multiply EVERY term by 10 to make every value a whole number.\r
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\n" ); document.write( "\n" ); document.write( "\"-20x%2B70y=-65\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%2840x-90y=105%2C-20x%2B70y=-65%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%28-20x%2B70y%29=2%28-65%29\" Multiply the both sides of the second equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"-40x%2B140y=-130\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%2840x-90y=105%2C-40x%2B140y=-130%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:\r
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\n" ); document.write( "\n" ); document.write( "\"%2840x-90y%29%2B%28-40x%2B140y%29=%28105%29%2B%28-130%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2840x-40x%29%2B%28-90y%2B140y%29=105%2B-130\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B50y=-25\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"50y=-25\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-25%29%2F%2850%29\" Divide both sides by \"50\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1%2F2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"40x-90y=105\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"40x-90%28-1%2F2%29=105\" Plug in \"y=-1%2F2\".\r
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\n" ); document.write( "\n" ); document.write( "\"40x%2B45=105\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"40x=105-45\" Subtract \"45\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"40x=60\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2860%29%2F%2840%29\" Divide both sides by \"40\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=3%2F2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=3%2F2\" and \"y=-1%2F2\".\r
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\n" ); document.write( "\n" ); document.write( "Which form the ordered pair .\r
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\n" ); document.write( "\n" ); document.write( "This means that the system is consistent and independent.
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