document.write( "Question 128458: how to write 12x + 3y = 6 in function form and then graph.
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Algebra.Com's Answer #94018 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
# 1\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B3y=6\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"3y=6-12x\" Subtract \"12+x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"3y=-12x%2B6\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-12x%2B6%29%2F%283%29\" Divide both sides by \"3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-12%2F3%29x%2B%286%29%2F%283%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=-4x%2B2\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the equation is now in slope-intercept form (\"y=mx%2Bb\") where the slope is \"m=-4\" and the y-intercept is \"b=2\"\r
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\n" ); document.write( "\n" ); document.write( "So to get the equation into function form, simply replace y with f(x)\r
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\n" ); document.write( "\n" ); document.write( "So the equation changes to the function \"f%28x%29=-4x%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"y=-4x%2B2\" we can see that the equation is in slope-intercept form \"y=mx%2Bb\" where the slope is \"m=-4\" and the y-intercept is \"b=2\" \r
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\n" ); document.write( "\n" ); document.write( "Since \"b=2\" this tells us that the y-intercept is .Remember the y-intercept is the point where the graph intersects with the y-axis\r
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\n" ); document.write( "\n" ); document.write( "So we have one point \r
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\n" ); document.write( "\n" ); document.write( "Now since the slope is comprised of the \"rise\" over the \"run\" this means\r
\n" ); document.write( "\n" ); document.write( "\"slope=rise%2Frun\"\r
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\n" ); document.write( "\n" ); document.write( "Also, because the slope is \"-4\", this means:\r
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\n" ); document.write( "\n" ); document.write( "\"rise%2Frun=-4%2F1\"\r
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\n" ); document.write( "\n" ); document.write( "which shows us that the rise is -4 and the run is 1. This means that to go from point to point, we can go down 4 and over 1\r
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\n" ); document.write( "\n" ); document.write( "So starting at , go down 4 units \r
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\n" ); document.write( "\n" ); document.write( "and to the right 1 unit to get to the next point \r
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\n" ); document.write( "\n" ); document.write( "Now draw a line through these points to graph \"y=-4x%2B2\"\r
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\n" ); document.write( "\n" ); document.write( " So this is the graph of \"y=-4x%2B2\" through the points and \r
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\n" ); document.write( "\n" ); document.write( "# 2\r
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\n" ); document.write( "\n" ); document.write( "\"4x-2y=16\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=16-4x\" Subtract \"4+x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=-4x%2B16\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-4x%2B16%29%2F%28-2%29\" Divide both sides by \"-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-4%2F-2%29x%2B%2816%29%2F%28-2%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-8\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the equation is now in slope-intercept form (\"y=mx%2Bb\") where the slope is \"m=2\" and the y-intercept is \"b=-8\"\r
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\n" ); document.write( "\n" ); document.write( "So to get the equation into function form, simply replace y with f(x)\r
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\n" ); document.write( "\n" ); document.write( "So the equation changes to the function \"f%28x%29=2x-8\"\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"y=2x-8\" we can see that the equation is in slope-intercept form \"y=mx%2Bb\" where the slope is \"m=2\" and the y-intercept is \"b=-8\" \r
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\n" ); document.write( "\n" ); document.write( "Since \"b=-8\" this tells us that the y-intercept is .Remember the y-intercept is the point where the graph intersects with the y-axis\r
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\n" ); document.write( "\n" ); document.write( "So we have one point \r
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\n" ); document.write( "\n" ); document.write( "Now since the slope is comprised of the \"rise\" over the \"run\" this means\r
\n" ); document.write( "\n" ); document.write( "\"slope=rise%2Frun\"\r
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\n" ); document.write( "\n" ); document.write( "Also, because the slope is \"2\", this means:\r
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\n" ); document.write( "\n" ); document.write( "\"rise%2Frun=2%2F1\"\r
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\n" ); document.write( "\n" ); document.write( "which shows us that the rise is 2 and the run is 1. This means that to go from point to point, we can go up 2 and over 1\r
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\n" ); document.write( "\n" ); document.write( "So starting at , go up 2 units \r
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\n" ); document.write( "\n" ); document.write( "and to the right 1 unit to get to the next point \r
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\n" ); document.write( "\n" ); document.write( "Now draw a line through these points to graph \"y=2x-8\"\r
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\n" ); document.write( "\n" ); document.write( " So this is the graph of \"y=2x-8\" through the points and
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