document.write( "Question 142430: Find an equation in slope-intercept form passing through the points (2,5) and
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Algebra.Com's Answer #103661 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
First lets find the slope through the points (\"2\",\"5\") and (\"7\",\"-3\")\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 (\"2\",\"5\") and is the second point (\"7\",\"-3\"))\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-3-5%29%2F%287-2%29\" Plug in \"y%5B2%5D=-3\",\"y%5B1%5D=5\",\"x%5B2%5D=7\",\"x%5B1%5D=2\" (these are the coordinates of given points)\r
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\n" ); document.write( "\n" ); document.write( "\"m=+-8%2F5\" Subtract the terms in the numerator \"-3-5\" to get \"-8\". Subtract the terms in the denominator \"7-2\" to get \"5\"\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=%28-8%2F5%29%28x-2%29\" Plug in \"m=-8%2F5\", \"x%5B1%5D=2\", and \"y%5B1%5D=5\" (these values are given)\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=%28-8%2F5%29x%2B%28-8%2F5%29%28-2%29\" Distribute \"-8%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=%28-8%2F5%29x%2B16%2F5\" Multiply \"-8%2F5\" and \"-2\" to get \"16%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-8%2F5%29x%2B16%2F5%2B5\" Add \"5\" to both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-8%2F5%29x%2B41%2F5\" Combine like terms \"16%2F5\" and \"5\" to get \"41%2F5\" (note: if you need help with combining fractions, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line which goes through the points (\"2\",\"5\") and (\"7\",\"-3\") is:\"y=%28-8%2F5%29x%2B41%2F5\"\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=-8%2F5\" and the y-intercept is \"b=41%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the equation \"y=%28-8%2F5%29x%2B41%2F5\" and plot the points (\"2\",\"5\") and (\"7\",\"-3\"), 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=%28-8%2F5%29x%2B41%2F5\" through the points (\"2\",\"5\") and (\"7\",\"-3\")\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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