document.write( "Question 840530: Find and equation of the line satisfying the given condition :\r
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Algebra.Com's Answer #506290 by jim_thompson5910(35256)\"\" \"About 
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Solved by pluggable solver: Finding the Equation of a Line
First lets find the slope through the points (\"-1\",\"-5\") and (\"3\",\"6\")
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\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: (\"x%5B1%5D\",\"y%5B1%5D\") is the first point (\"-1\",\"-5\") and (\"x%5B2%5D\",\"y%5B2%5D\") is the second point (\"3\",\"6\"))
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\n" ); document.write( " \"m=%286--5%29%2F%283--1%29\" Plug in \"y%5B2%5D=6\",\"y%5B1%5D=-5\",\"x%5B2%5D=3\",\"x%5B1%5D=-1\" (these are the coordinates of given points)
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\n" ); document.write( " \"m=+11%2F4\" Subtract the terms in the numerator \"6--5\" to get \"11\". Subtract the terms in the denominator \"3--1\" to get \"4\"
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\n" ); document.write( " So the slope is
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\n" ); document.write( " \"m=11%2F4\"
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\n" ); document.write( "Now let's use the point-slope formula to find the equation of the line:
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\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 (\"x%5B1%5D\",\"y%5B1%5D\") is one of the given points
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\n" ); document.write( " So lets use the Point-Slope Formula to find the equation of the line
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\n" ); document.write( " \"y--5=%2811%2F4%29%28x--1%29\" Plug in \"m=11%2F4\", \"x%5B1%5D=-1\", and \"y%5B1%5D=-5\" (these values are given)
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\n" ); document.write( " \"y%2B5=%2811%2F4%29%28x--1%29\" Rewrite \"y--5\" as \"y%2B5\"
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\n" ); document.write( " \"y%2B5=%2811%2F4%29%28x%2B1%29\" Rewrite \"x--1\" as \"x%2B1\"
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\n" ); document.write( " \"y%2B5=%2811%2F4%29x%2B%2811%2F4%29%281%29\" Distribute \"11%2F4\"
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\n" ); document.write( " \"y%2B5=%2811%2F4%29x%2B11%2F4\" Multiply \"11%2F4\" and \"1\" to get \"11%2F4\"
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\n" ); document.write( " \"y=%2811%2F4%29x%2B11%2F4-5\" Subtract \"5\" from both sides to isolate y
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\n" ); document.write( " \"y=%2811%2F4%29x-9%2F4\" Combine like terms \"11%2F4\" and \"-5\" to get \"-9%2F4\" (note: if you need help with combining fractions, check out this solver)
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\n" ); document.write( " Answer:
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\n" ); document.write( " So the equation of the line which goes through the points (\"-1\",\"-5\") and (\"3\",\"6\") is:\"y=%2811%2F4%29x-9%2F4\"
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\n" ); document.write( " The equation is now in \"y=mx%2Bb\" form (which is slope-intercept form) where the slope is \"m=11%2F4\" and the y-intercept is \"b=-9%2F4\"
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\n" ); document.write( " Notice if we graph the equation \"y=%2811%2F4%29x-9%2F4\" and plot the points (\"-1\",\"-5\") and (\"3\",\"6\"), we get this: (note: if you need help with graphing, check out this solver)
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\n" ); document.write( " Graph of \"y=%2811%2F4%29x-9%2F4\" through the points (\"-1\",\"-5\") and (\"3\",\"6\")
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\n" ); document.write( " Notice how the two points lie on the line. This graphically verifies our answer.
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