document.write( "Question 162022: Find an equation of the line containing the given pair of points. Express you answer in the form
\n" ); document.write( "x=a, y=b, or mx+b.\r
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Algebra.Com's Answer #119404 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Finding the Equation of a Line
First lets find the slope through the points (\"-4\",\"-4\") and (\"6\",\"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 (\"-4\",\"-4\") and (\"x%5B2%5D\",\"y%5B2%5D\") is the second point (\"6\",\"6\"))
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\n" ); document.write( " \"m=%286--4%29%2F%286--4%29\" Plug in \"y%5B2%5D=6\",\"y%5B1%5D=-4\",\"x%5B2%5D=6\",\"x%5B1%5D=-4\" (these are the coordinates of given points)
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\n" ); document.write( " \"m=+10%2F10\" Subtract the terms in the numerator \"6--4\" to get \"10\". Subtract the terms in the denominator \"6--4\" to get \"10\"
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\n" ); document.write( " \"m=1\" Reduce
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\n" ); document.write( " So the slope is
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\n" ); document.write( " \"m=1\"
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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--4=%281%29%28x--4%29\" Plug in \"m=1\", \"x%5B1%5D=-4\", and \"y%5B1%5D=-4\" (these values are given)
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\n" ); document.write( " \"y%2B4=%281%29%28x--4%29\" Rewrite \"y--4\" as \"y%2B4\"
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\n" ); document.write( " \"y%2B4=%281%29%28x%2B4%29\" Rewrite \"x--4\" as \"x%2B4\"
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\n" ); document.write( " \"y%2B4=1x%2B%281%29%284%29\" Distribute \"1\"
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\n" ); document.write( " \"y%2B4=1x%2B4\" Multiply \"1\" and \"4\" to get \"4%2F1\". Now reduce \"4%2F1\" to get \"4\"
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\n" ); document.write( " \"y=1x%2B4-4\" Subtract \"4\" from both sides to isolate y
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\n" ); document.write( " \"y=1x%2B0\" Combine like terms \"4\" and \"-4\" to get \"0\"
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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 (\"-4\",\"-4\") and (\"6\",\"6\") is:\"y=1x%2B0\"
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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=1\" and the y-intercept is \"b=0\"
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\n" ); document.write( " Notice if we graph the equation \"y=1x%2B0\" and plot the points (\"-4\",\"-4\") and (\"6\",\"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=1x%2B0\" through the points (\"-4\",\"-4\") and (\"6\",\"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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\n" ); document.write( "\n" ); document.write( "So the equation is simply \"y=x\"
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