document.write( "Question 750887: write the equation of the line passing through the points (8,-39) and (1,3) \n" ); document.write( "
Algebra.Com's Answer #456864 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( "First let's find the slope of the line through the points and \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Note: is the first point . So this means that \"x%5B1%5D=8\" and \"y%5B1%5D=-39\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=1\" and \"y%5B2%5D=3\".\r
\n" ); document.write( "
\n" ); document.write( "
\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
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=%283--39%29%2F%281-8%29\" Plug in \"y%5B2%5D=3\", \"y%5B1%5D=-39\", \"x%5B2%5D=1\", and \"x%5B1%5D=8\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=%2842%29%2F%281-8%29\" Subtract \"-39\" from \"3\" to get \"42\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=%2842%29%2F%28-7%29\" Subtract \"8\" from \"1\" to get \"-7\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"m=-6\" Reduce\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the slope of the line that goes through the points and is \"m=-6\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now let's use the point slope formula:\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y-y%5B1%5D=m%28x-x%5B1%5D%29\" Start with the point slope formula\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y--39=-6%28x-8%29\" Plug in \"m=-6\", \"x%5B1%5D=8\", and \"y%5B1%5D=-39\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y%2B39=-6%28x-8%29\" Rewrite \"y--39\" as \"y%2B39\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y%2B39=-6x%2B-6%28-8%29\" Distribute\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y%2B39=-6x%2B48\" Multiply\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y=-6x%2B48-39\" Subtract 39 from both sides. \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y=-6x%2B9\" Combine like terms. \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=-6x%2B9\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );