document.write( "Question 146541: Please write the linear function for which f (3) =6 and f (-4) =2\r
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Algebra.Com's Answer #106974 by jim_thompson5910(35256)\"\" \"About 
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f (3) =6 tells us that when x=3, then y=6. So we know that the equation goes through the point (3,6)\r
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\n" ); document.write( "\n" ); document.write( "f (-4) =2 tells us that when x=-4, then y=2. So we know that the equation goes through the point (-4,2)\r
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\n" ); document.write( "\n" ); document.write( "So let's find the equation of the line that goes through the points (3,6) and (-4,2)\r
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\n" ); document.write( "\n" ); document.write( "First let's find the slope through the points and \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=%282-6%29%2F%28-4-3%29\" Plug in \"y%5B2%5D=2\", \"y%5B1%5D=6\", \"x%5B2%5D=-4\", \"x%5B1%5D=3\", , \r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-4%29%2F%28-4-3%29\" Subtract \"6\" from \"2\" to get \"-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-4%29%2F%28-7%29\" Subtract \"3\" from \"-4\" to get \"-7\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=4%2F7\" 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=4%2F7\"\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-6=%284%2F7%29%28x-3%29\" Plug in \"m=4%2F7\", \"x%5B1%5D=3\", and \"y%5B1%5D=6\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-6=%284%2F7%29x%2B%284%2F7%29%28-3%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-6=%284%2F7%29x-12%2F7\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%284%2F7%29x-12%2F7%2B6\" Add 6 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%284%2F7%29x%2B30%2F7\" 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( "\"y=%284%2F7%29x%2B30%2F7\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=%284%2F7%29x%2B30%2F7\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=%284%2F7%29x%2B30%2F7\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=%284%2F7%29x%2B30%2F7\" through the points and \r
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