document.write( "Question 636408: Write the equation of the line if it is joined by the two points (1, -3) and (4, -2) \n" ); document.write( "
Algebra.Com's Answer #401003 by jim_thompson5910(35256)\"\" \"About 
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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=-3\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=4\" 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=%28-2--3%29%2F%284-1%29\" Plug in \"y%5B2%5D=-2\", \"y%5B1%5D=-3\", \"x%5B2%5D=4\", and \"x%5B1%5D=1\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%281%29%2F%284-1%29\" Subtract \"-3\" from \"-2\" to get \"1\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%281%29%2F%283%29\" Subtract \"1\" from \"4\" to get \"3\"\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%2F3\"\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--3=%281%2F3%29%28x-1%29\" Plug in \"m=1%2F3\", \"x%5B1%5D=1\", and \"y%5B1%5D=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B3=%281%2F3%29%28x-1%29\" Rewrite \"y--3\" as \"y%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B3=%281%2F3%29x%2B%281%2F3%29%28-1%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B3=%281%2F3%29x-1%2F3\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F3%29x-1%2F3-3\" Subtract 3 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F3%29x-10%2F3\" 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%2F3%29x-10%2F3\"\r
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