document.write( "Question 146532: Solve the system of Equations\r
\n" ); document.write( "\n" ); document.write( "2/5x + 3/5y = 16/5
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\n" ); document.write( "\n" ); document.write( "I know that some way you have to eliminate the fractions in the first equations. Where I am stuck at is how to eliminate the fractions and what type of method to use to solve it.
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Algebra.Com's Answer #106963 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%28%282%2F5%29x+%2B+%283%2F5%29y+=+16%2F5%2C4x+%2B+2y+=+40%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"5%28%282%2Fcross%285%29%29x+%2B+%283%2Fcross%285%29%29y+%29=5%28+16%2Fcross%285%29%29\" Multiply the both sides of the first equation by the LCD 5.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B3y=16\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2%282x%2B3y%29=-2%2816%29\" Now multiply the both sides of the first equation by -2.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-6y=-32\" 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%28-4x-6y=-32%2C4x%2B2y=40%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( "\"%28-4x-6y%29%2B%284x%2B2y%29=%28-32%29%2B%2840%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-4x%2B4x%29%2B%28-6y%2B2y%29=-32%2B40\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-4y=8\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=8\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%288%29%2F%28-4%29\" Divide both sides by \"-4\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-6y=-32\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-6%28-2%29=-32\" Plug in \"y=-2\".\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2B12=-32\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x=-32-12\" Subtract \"12\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x=-44\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-44%29%2F%28-4%29\" Divide both sides by \"-4\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=11\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=11\" and \"y=-2\".\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 two equations are 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 \"%282%2F5%29x+%2B+%283%2F5%29y+=+16%2F5\" (red) and \"4x+%2B+2y+=+40\" (green) \r
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