document.write( "Question 175658: Please help me solve this equation: Pat invested a total of $3,000. Part of the money yields 10 percent interest
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Algebra.Com's Answer #130757 by jim_thompson5910(35256)\"\" \"About 
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Let x=amount invested at 10% and y=amount invested at 8%\r
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\n" ); document.write( "\n" ); document.write( "\"Pat invested a total of $3,000\" translates to \"x%2By=3000\"\r
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\n" ); document.write( "\n" ); document.write( "\"Part of the money yields 10 percent interest
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\n" ); document.write( "interest from this investment is $256\" translates to \"0.10x%2B0.08y=256\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply both sides by 100 to get \"10x%2B8y=25600\"\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%28x%2By=3000%2C10x%2B8y=25600%29\"\r
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\n" ); document.write( "\n" ); document.write( "Let's solve by substitution\r
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\n" ); document.write( "\n" ); document.write( "Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to solve for y.\r
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\n" ); document.write( "\n" ); document.write( "So let's isolate y in the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%2By=3000\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=3000-x\" Subtract \"x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B3000\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=-x%2B3000\", we can now replace each \"y\" in the second equation with \"-x%2B3000\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"10x%2B8highlight%28%28-x%2B3000%29%29=25600\" Plug in \"y=-x%2B3000\" into the second equation. In other words, replace each \"y\" with \"-x%2B3000\". Notice we've eliminated the \"y\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"10x%2B%288%29%28-1%29x%2B%288%29%283000%29=25600\" Distribute \"8\" to \"-x%2B3000\"\r
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\n" ); document.write( "\n" ); document.write( "\"10x-8x%2B24000=25600\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B24000=25600\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"2x=25600-24000\"Subtract 24000 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2x=1600\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%281600%29%2F%282%29\" Divide both sides by 2 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=800\" Divide\r
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\n" ); document.write( "\n" ); document.write( "-----------------First Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the first part of our answer is: \"x=800\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=800\" we can plug it into the equation \"y=-x%2B3000\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B3000\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%28800%29%2B3000\" Plug in \"x=800\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-800%2B3000\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=2200\" Combine like terms \r
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\n" ); document.write( "\n" ); document.write( "-----------------Second Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the second part of our answer is: \"y=2200\"\r
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\n" ); document.write( "\n" ); document.write( "-----------------Summary------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So our answers are:\r
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\n" ); document.write( "\n" ); document.write( "\"x=800\" and \"y=2200\"\r
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\n" ); document.write( "\n" ); document.write( "So this means that Pat invested $800 at 10% and $2,200 at 8%
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