document.write( "Question 113890: Write the equation of the line passing through (6, –5) and (–3, 4) \n" ); document.write( "
Algebra.Com's Answer #82878 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
First lets find the slope through the points (\"6\",\"-5\") and (\"-3\",\"4\")\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 (note: is the first point (\"6\",\"-5\") and is the second point (\"-3\",\"4\"))\r
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\n" ); document.write( "\n" ); document.write( "\"m=%284--5%29%2F%28-3-6%29\" Plug in \"y%5B2%5D=4\",\"y%5B1%5D=-5\",\"x%5B2%5D=-3\",\"x%5B1%5D=6\" (these are the coordinates of given points)\r
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\n" ); document.write( "\n" ); document.write( "\"m=+9%2F-9\" Subtract the terms in the numerator \"4--5\" to get \"9\". Subtract the terms in the denominator \"-3-6\" to get \"-9\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-1\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the slope is\r
\n" ); document.write( "\n" ); document.write( "\"m=-1\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's use the point-slope formula to find the equation of the line:\r
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\n" ); document.write( "\n" ); document.write( "------Point-Slope Formula------
\n" ); document.write( "\"y-y%5B1%5D=m%28x-x%5B1%5D%29\" where \"m\" is the slope, and is one of the given points\r
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\n" ); document.write( "\n" ); document.write( "So lets use the Point-Slope Formula to find the equation of the line\r
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\n" ); document.write( "\n" ); document.write( "\"y--5=%28-1%29%28x-6%29\" Plug in \"m=-1\", \"x%5B1%5D=6\", and \"y%5B1%5D=-5\" (these values are given)\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=%28-1%29%28x-6%29\" Rewrite \"y--5\" as \"y%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=-x%2B%28-1%29%28-6%29\" Distribute \"-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=-x%2B6\" Multiply \"-1\" and \"-6\" to get \"6\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B6-5\" Subtract \"5\" from both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B1\" Combine like terms \"6\" and \"-5\" to get \"1\" \r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line which goes through the points (\"6\",\"-5\") and (\"-3\",\"4\") is:\"y=-x%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "The equation is now in \"y=mx%2Bb\" form (which is slope-intercept form) where the slope is \"m=-1\" and the y-intercept is \"b=1\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the equation \"y=-x%2B1\" and plot the points (\"6\",\"-5\") and (\"-3\",\"4\"), we get this: (note: if you need help with graphing, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=-x%2B1\" through the points (\"6\",\"-5\") and (\"-3\",\"4\")\r
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\n" ); document.write( "\n" ); document.write( "Notice how the two points lie on the line. This graphically verifies our answer.
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