document.write( "Question 282618: 3x - 6y = -3 and 2x + 4y = 30 \n" ); document.write( "
Algebra.Com's Answer #205203 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%283x-6y=-3%2C2x%2B4y=30%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%283x-6y%29=2%28-3%29\" Multiply the both sides of the first equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"6x-12y=-6\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"3%282x%2B4y%29=3%2830%29\" Multiply the both sides of the second equation by 3.\r
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\n" ); document.write( "\n" ); document.write( "\"6x%2B12y=90\" 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-12y=-6%2C6x%2B12y=90%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-12y%29%2B%286x%2B12y%29=%28-6%29%2B%2890%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%286x%2B6x%29%2B%28-12y%2B12y%29=-6%2B90\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B0y=84\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"12x=84\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2884%29%2F%2812%29\" Divide both sides by \"12\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=7\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"6x-12y=-6\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"6%287%29-12y=-6\" Plug in \"x=7\".\r
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\n" ); document.write( "\n" ); document.write( "\"42-12y=-6\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-12y=-6-42\" Subtract \"42\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-12y=-48\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-48%29%2F%28-12%29\" Divide both sides by \"-12\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=4\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=7\" and \"y=4\".\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 \"3x-6y=-3\" (red) and \"2x%2B4y=30\" (green)
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