document.write( "Question 609962: Find the equation for a line which passes through the points (-3,9) and (1,1). Write the equation in slope-intercept form. Please show work.
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Algebra.Com's Answer #384040 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=9\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=1\" and \"y%5B2%5D=1\".\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=%281-9%29%2F%281--3%29\" Plug in \"y%5B2%5D=1\", \"y%5B1%5D=9\", \"x%5B2%5D=1\", and \"x%5B1%5D=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-8%29%2F%281--3%29\" Subtract \"9\" from \"1\" to get \"-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-8%29%2F%284%29\" Subtract \"-3\" from \"1\" to get \"4\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-2\" 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=-2\"\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-9=-2%28x--3%29\" Plug in \"m=-2\", \"x%5B1%5D=-3\", and \"y%5B1%5D=9\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-9=-2%28x%2B3%29\" Rewrite \"x--3\" as \"x%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-9=-2x%2B-2%283%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-9=-2x-6\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x-6%2B9\" Add 9 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B3\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=-2x%2B3\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=-2x%2B3\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=-2x%2B3\" through the points and \r
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\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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