document.write( "Question 93845: find the equation of the line through(-5,8)and parallel to the line 4x+y=8 \n" ); document.write( "
Algebra.Com's Answer #68356 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
First convert 4x+y=8 into slope intercept form\r
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Solved by pluggable solver: Converting Linear Equations in Standard form to Slope-Intercept Form (and vice versa)
Convert from standard form (Ax+By = C) to slope-intercept form (y = mx+b)


\"4x%2B1y=8\" Start with the given equation


\"4x%2B1y-4x=8-4x\" Subtract 4x from both sides


\"1y=-4x%2B8\" Simplify


The original equation \"4x%2B1y=8\" (standard form) is equivalent to \"y+=+-4x%2B8\" (slope-intercept form)


The equation \"y+=+-4x%2B8\" is in the form \"y=mx%2Bb\" where \"m=-4\" is the slope and \"b=8\" is the y intercept.



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\n" ); document.write( "\n" ); document.write( "Now lets find the parallel line \r
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Solved by pluggable solver: Finding the Equation of a Line Parallel or Perpendicular to a Given Line

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\n" ); document.write( " Since any two parallel lines have the same slope we know the slope of the unknown line is \"-4\" (its from the slope of \"y=-4%2Ax%2B8\" which is also \"-4\").\n" ); document.write( "Also since the unknown line goes through (-5,8), we can find the equation by plugging in this info into the point-slope formula
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\n" ); document.write( " Point-Slope Formula:
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\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 the given point
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\n" ); document.write( " \"y-8=-4%2A%28x%2B5%29\" Plug in \"m=-4\", \"x%5B1%5D=-5\", and \"y%5B1%5D=8\"
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\n" ); document.write( " \"y-8=-4%2Ax%2B%284%29%28-5%29\" Distribute \"-4\"
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\n" ); document.write( " \"y-8=-4%2Ax-20\" Multiply
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\n" ); document.write( " \"y=-4%2Ax-20%2B8\"Add \"8\" to both sides to isolate y
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\n" ); document.write( " \"y=-4%2Ax-12\" Combine like terms
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\n" ); document.write( " So the equation of the line that is parallel to \"y=-4%2Ax%2B8\" and goes through (\"-5\",\"8\") is \"y=-4%2Ax-12\"
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\n" ); document.write( " So here are the graphs of the equations \"y=-4%2Ax%2B8\" and \"y=-4%2Ax-12\"
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\n" ); document.write( " graph of the given equation \"y=-4%2Ax%2B8\" (red) and graph of the line \"y=-4%2Ax-12\"(green) that is parallel to the given graph and goes through (\"-5\",\"8\")
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