document.write( "Question 117941: Find the slope of any line parallel to the line through points (15,1) and (4,2). Thanks for your help. \n" ); document.write( "
Algebra.Com's Answer #85956 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
first find equation of the line through points (\"15\",\"1\") and (\"4\",\"2\")in \"slope-intercept\" form \r
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Solved by pluggable solver: FIND EQUATION of straight line given 2 points
hahaWe are trying to find equation of form y=ax+b, where a is slope, and b is intercept, which passes through points (x1, y1) = (15, 1) and (x2, y2) = (4, 2).
\n" ); document.write( " Slope a is .
\n" ); document.write( " Intercept is found from equation \"a%2Ax%5B1%5D%2Bb+=+y%5B1%5D\", or \"-0.0909090909090909%2A15+%2Bb+=+2.36363636363636\". From that,
\n" ); document.write( " intercept b is \"b=y%5B1%5D-a%2Ax%5B1%5D\", or \"b=1--0.0909090909090909%2A15+=+2.36363636363636\".
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\n" ); document.write( " y=(-0.0909090909090909)x + (2.36363636363636)
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\n" ); document.write( " Your graph:
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\n" ); document.write( "\n" ); document.write( "the \"slope\" of any line parallel to this line with slope \"a=0.09\" will be \"a%5B1%5D=0.09\" because \"parallel\" lines have \"equal\"\"+slopes\"\r
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\n" ); document.write( "\n" ); document.write( "if we take \"y%5B1%5D=0.9+%2B+6\" as the line parallel to the line through given points, then we have :\r
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Solved by pluggable solver: Solve the System of Equations by Graphing

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\n" ); document.write( " Start with the given system of equations:
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\n" ); document.write( " \"09x%2By=236\"
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\n" ); document.write( " \"09x%2By=6\"
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\n" ); document.write( " In order to graph these equations, we need to solve for y for each equation.
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\n" ); document.write( " So let's solve for y on the first equation
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\n" ); document.write( " \"09x%2By=236\" Start with the given equation
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\n" ); document.write( " \"1y=236-09x\" Subtract \"09+x\" from both sides
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\n" ); document.write( " \"1y=-09x%2B236\" Rearrange the equation
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\n" ); document.write( " \"y=%28-09x%2B236%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28-09%2F1%29x%2B%28236%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=-9x%2B236\" Reduce
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\n" ); document.write( " Now lets graph \"y=-9x%2B236\" (note: if you need help with graphing, check out this solver)
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\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-9x%2B236%29+\" Graph of \"y=-9x%2B236\"
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\n" ); document.write( " So let's solve for y on the second equation
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\n" ); document.write( " \"09x%2By=6\" Start with the given equation
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\n" ); document.write( " \"1y=6-09x\" Subtract \"09+x\" from both sides
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\n" ); document.write( " \"1y=-09x%2B6\" Rearrange the equation
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\n" ); document.write( " \"y=%28-09x%2B6%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28-09%2F1%29x%2B%286%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=-9x%2B6\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=-9x%2B6\" to our first plot to get:
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\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-9x%2B236%2C-9x%2B6%29+\" Graph of \"y=-9x%2B236\"(red) and \"y=-9x%2B6\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines are parallel and will never intersect. So there are no solutions and the system is inconsistent.

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