document.write( "Question 553253: Find an equation for the linear function f for which f(3)=7 and f(-1)=5. \n" ); document.write( "
Algebra.Com's Answer #360753 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "First let's find the slope of the line through the points and \r
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\n" ); document.write( "\n" ); document.write( "Note: is the first point . So this means that \"x%5B1%5D=3\" and \"y%5B1%5D=7\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=-1\" and \"y%5B2%5D=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\" Start with the slope formula.\r
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\n" ); document.write( "\n" ); document.write( "\"m=%285-7%29%2F%28-1-3%29\" Plug in \"y%5B2%5D=5\", \"y%5B1%5D=7\", \"x%5B2%5D=-1\", and \"x%5B1%5D=3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-2%29%2F%28-1-3%29\" Subtract \"7\" from \"5\" to get \"-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-2%29%2F%28-4%29\" Subtract \"3\" from \"-1\" to get \"-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=1%2F2\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the slope of the line that goes through the points and is \"m=1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's use the point slope formula:\r
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\n" ); document.write( "\n" ); document.write( "\"y-y%5B1%5D=m%28x-x%5B1%5D%29\" Start with the point slope formula\r
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\n" ); document.write( "\n" ); document.write( "\"y-7=%281%2F2%29%28x-3%29\" Plug in \"m=1%2F2\", \"x%5B1%5D=3\", and \"y%5B1%5D=7\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-7=%281%2F2%29x%2B%281%2F2%29%28-3%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-7=%281%2F2%29x-3%2F2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x-3%2F2%2B7\" Add 7 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x%2B11%2F2\" Combine like terms. note: If you need help with fractions, check out this solver.\r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=%281%2F2%29x%2B11%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you\r
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\n" ); document.write( "\n" ); document.write( "Jim\r
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