document.write( "Question 847706: Find an equation of the line containing the points (1, -1) and (3, 2). \n" ); document.write( "
Algebra.Com's Answer #510654 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=1\" and \"y%5B1%5D=-1\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=3\" and \"y%5B2%5D=2\".\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--1%29%2F%283-1%29\" Plug in \"y%5B2%5D=2\", \"y%5B1%5D=-1\", \"x%5B2%5D=3\", and \"x%5B1%5D=1\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%283%29%2F%283-1%29\" Subtract \"-1\" from \"2\" to get \"3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%283%29%2F%282%29\" Subtract \"1\" from \"3\" to get \"2\"\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=3%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--1=%283%2F2%29%28x-1%29\" Plug in \"m=3%2F2\", \"x%5B1%5D=1\", and \"y%5B1%5D=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B1=%283%2F2%29%28x-1%29\" Rewrite \"y--1\" as \"y%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B1=%283%2F2%29x%2B%283%2F2%29%28-1%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B1=%283%2F2%29x-3%2F2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%2F2%29x-3%2F2-1\" Subtract 1 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%2F2%29x-5%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=%283%2F2%29x-5%2F2\"\r
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