document.write( "Question 194039: Please help. I need to find the equation of the line through (-3,1) with a slope of -1/3.\r
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Algebra.Com's Answer #145632 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "If you want to find the equation of line with a given a slope of \"-1%2F3\" which goes through the point (-3,1), you can simply use the point-slope formula to find the equation:\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 the given point\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-1=%28-1%2F3%29%28x--3%29\" Plug in \"m=-1%2F3\", \"x%5B1%5D=-3\", and \"y%5B1%5D=1\" (these values are given)\r
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\n" ); document.write( "\n" ); document.write( "\"y-1=%28-1%2F3%29%28x%2B3%29\" Rewrite \"x--3\" as \"x%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-1=%28-1%2F3%29x%2B%28-1%2F3%29%283%29\" Distribute \"-1%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-1=%28-1%2F3%29x-1\" Multiply \"-1%2F3\" and \"3\" to get \"-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F3%29x-1%2B1\" Add 1 to both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F3%29x%2B0\" Combine like terms \"-1\" and \"1\" to get \"0\" \r
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\n" ); document.write( "\n" ); document.write( "\"y=-%281%2F3%29x\" Simplify\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 with a slope of \"-1%2F3\" which goes through the point (-3,1) is:\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F3%29x%2B0\" which is now in \"y=mx%2Bb\" form where the slope is \"m=-1%2F3\" and the y-intercept is \"b=0\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the equation \"y=%28-1%2F3%29x%2B0\" and plot the point (-3,1), we get (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=%28-1%2F3%29x\" through the point (-3,1)\r
\n" ); document.write( "\n" ); document.write( "and we can see that the point lies on the line. Since we know the equation has a slope of \"-1%2F3\" and goes through the point (-3,1), this verifies our answer.
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