document.write( "Question 201739: How do you solve the systems of linear equations using the graphing method?
\n" ); document.write( "I understand the elimination method and etc., but I do not get how to solve using the graphing method.\r
\n" ); document.write( "\n" ); document.write( "I know that the first step is putting it in slope-intercept form, but the graphing part I am having trouble with. How do you graph it exactly? Is there a specific way to plot points?\r
\n" ); document.write( "\n" ); document.write( "For example, how do you solve for this:\r
\n" ); document.write( "\n" ); document.write( "4x+2y=8
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\n" ); document.write( "\n" ); document.write( "So far I tried doing it, and I've gotten the answer (3,2) but I did it again and there was no solution because it was parrallel.
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Algebra.Com's Answer #151974 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Step 1: Graph \"4x%2B2y=8\"\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B2y=8\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=8-4x\" Subtract \"4x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=-4x%2B8\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-4x%2B8%29%2F%282%29\" Divide both sides by \"2\" to isolate y.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-4%29%2F%282%29%29x%2B%288%29%2F%282%29\" Break up the fraction.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B4\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"y=-2x%2B4\" 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=4\" \r
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\n" ); document.write( "\n" ); document.write( "Since \"b=4\" 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 down 2 and over 1\r
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\n" ); document.write( "\n" ); document.write( "So starting at , go down 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%2B4\"\r
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\n" ); document.write( "\n" ); document.write( " So this is the graph of \"y=-2x%2B4\" (which is also \"4x%2B2y=8\") through the points and \r
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\n" ); document.write( "\n" ); document.write( "Step 2: Graph \"y=-2x%2B6\"\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"y=-2x%2B6\" 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=6\" \r
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\n" ); document.write( "\n" ); document.write( "Since \"b=6\" 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( "\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 down 2 and over 1\r
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\n" ); document.write( "\n" ); document.write( "So starting at , go down 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%2B6\"\r
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\n" ); document.write( "\n" ); document.write( " So this is the graph of \"y=-2x%2B6\" through the points and \r
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\n" ); document.write( "\n" ); document.write( "Step 3: Graph the two equations together on the same coordinate plane\r
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\n" ); document.write( "\n" ); document.write( "Graph of \"4x%2B2y=8\" (red) and \"y=-2x%2B6\" (green). \r
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\n" ); document.write( "\n" ); document.write( "From the graph, we can see that the two lines are parallel and will NEVER cross. \r
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\n" ); document.write( "\n" ); document.write( "So this means that there are no solutions.\r
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\n" ); document.write( "\n" ); document.write( "So the system is inconsistent.
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