document.write( "Question 183031: HELP. Use elimination to solve each system of equations. 2X+2/3Y =4 X-1/2Y=7 \n" ); document.write( "
Algebra.Com's Answer #137403 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"2x%2B%282%2F3%29y+=4\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3%282x%29%2Bcross%283%29%28%282%2Fcross%283%29%29y%29=3%284%29\" Multiply EVERY term by the LCD \"3\" to clear any fractions.\r
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\n" ); document.write( "\n" ); document.write( "\"6x%2B2y=12\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"x-%281%2F2%29y=7\" Move onto the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%29-cross%282%29%28%281%2Fcross%282%29%29y%29=2%287%29\" Multiply EVERY term by the LCD \"2\" to clear any fractions.\r
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\n" ); document.write( "\n" ); document.write( "\"2x-y=14\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%286x%2B2y=12%2C2x-y=14%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%282x-y%29=2%2814%29\" Multiply the both sides of the second equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"4x-2y=28\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%286x%2B2y=12%2C4x-2y=28%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( "\"%286x%2B2y%29%2B%284x-2y%29=%2812%29%2B%2828%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%286x%2B4x%29%2B%282y%2B-2y%29=12%2B28\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"10x%2B0y=40\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"10x=40\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2840%29%2F%2810%29\" Divide both sides by \"10\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=4\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"6x%2B2y=12\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"6%284%29%2B2y=12\" Plug in \"x=4\".\r
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\n" ); document.write( "\n" ); document.write( "\"24%2B2y=12\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=12-24\" Subtract \"24\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=-12\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-12%29%2F%282%29\" Divide both sides by \"2\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-6\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=4\" and \"y=-6\".\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.\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 \"6x%2B2y=12\" (red) and \"2x-y=14\" (green) \r
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