document.write( "Question 112069: Write the equation of the line passing through (–3, –5) and (3, 0). \n" ); document.write( "
Algebra.Com's Answer #81762 by jim_thompson5910(35256)\"\" \"About 
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First lets find the slope through the points (\"-3\",\"-5\") and (\"3\",\"0\")\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 (\"-3\",\"-5\") and is the second point (\"3\",\"0\"))\r
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\n" ); document.write( "\n" ); document.write( "\"m=%280--5%29%2F%283--3%29\" Plug in \"y%5B2%5D=0\",\"y%5B1%5D=-5\",\"x%5B2%5D=3\",\"x%5B1%5D=-3\" (these are the coordinates of given points)\r
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\n" ); document.write( "\n" ); document.write( "\"m=+5%2F6\" Subtract the terms in the numerator \"0--5\" to get \"5\". Subtract the terms in the denominator \"3--3\" to get \"6\"\r
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\n" ); document.write( "\n" ); document.write( "So the slope is\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=%285%2F6%29%28x--3%29\" Plug in \"m=5%2F6\", \"x%5B1%5D=-3\", and \"y%5B1%5D=-5\" (these values are given)\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=%285%2F6%29%28x--3%29\" Rewrite \"y--5\" as \"y%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=%285%2F6%29%28x%2B3%29\" Rewrite \"x--3\" as \"x%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=%285%2F6%29x%2B%285%2F6%29%283%29\" Distribute \"5%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=%285%2F6%29x%2B5%2F2\" Multiply \"5%2F6\" and \"3\" to get \"15%2F6\". Now reduce \"15%2F6\" to get \"5%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%285%2F6%29x%2B5%2F2-5\" Subtract \"5\" from both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=%285%2F6%29x-5%2F2\" Combine like terms \"5%2F2\" and \"-5\" to get \"-5%2F2\" (note: if you need help with combining fractions, check out this solver)\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 (\"-3\",\"-5\") and (\"3\",\"0\") is:\"y=%285%2F6%29x-5%2F2\"\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=5%2F6\" and the y-intercept is \"b=-5%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the equation \"y=%285%2F6%29x-5%2F2\" and plot the points (\"-3\",\"-5\") and (\"3\",\"0\"), 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=%285%2F6%29x-5%2F2\" through the points (\"-3\",\"-5\") and (\"3\",\"0\")\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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