document.write( "Question 150559: I'm supposed to put the following formulas in y=mx+b form. Then I'm supposed to plot the Y intercept. Then to get the 2nd point I need to plot the rise and run of the two formulas. Last I need to give the point at which the two lines intersect. When I try these steps, it's not coming out right on my graph.\r
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\n" ); document.write( "\n" ); document.write( "Plot the intersect points of the two equations
\n" ); document.write( "2x + y = 4
\n" ); document.write( "3x - 4y = 6
\n" ); document.write( "Answer in book is (2,0)
\n" ); document.write( "When I change the equations I get the following;
\n" ); document.write( "y = -2x/1 -4
\n" ); document.write( "y = 3/4x - 6/4 (I divided equation by -4 to get this solution)\r
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\n" ); document.write( "\n" ); document.write( "Plot the intersect points of the two equations
\n" ); document.write( "x + 3y = -6
\n" ); document.write( "x - 3y = 0
\n" ); document.write( "Answer in book is (-3,-1)
\n" ); document.write( "When I change the equations I get the following;
\n" ); document.write( "y = -1/3x - 2 (I divided equation by 3 to get this solution)
\n" ); document.write( "y = 1/3x + 0 (I divided equation by -3 to get this solution)\r
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\n" ); document.write( "\n" ); document.write( "Plot the intersect points of the two equations
\n" ); document.write( "3x - 2y = -6
\n" ); document.write( "-6x + 4y = 9
\n" ); document.write( "Answer in book is No solution
\n" ); document.write( "When I change the equations I get the following;
\n" ); document.write( "y = 3/2x + 3 (I divided equation by -2 to get this solution)
\n" ); document.write( "y = 3/2x + 9/4 (I divided equation by 4 to get this solution)\r
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\n" ); document.write( "\n" ); document.write( "Plot the intersect points of the two equations
\n" ); document.write( "x + 2y = 4
\n" ); document.write( "-2x - 4y = -8
\n" ); document.write( "Answer in book is Infinite
\n" ); document.write( "When I change the equations I get the following;
\n" ); document.write( "y = -1/2x + 2 (I divided equation by 2 to get this solution)
\n" ); document.write( "y = 1/-2x + 2 (I divided equation by -4 to get this solution)
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Algebra.Com's Answer #110520 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'll do the first one to get you started\r
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\n" ); document.write( "\n" ); document.write( "First let's graph the equation \"2x+%2B+y+=+4\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x+%2B+y+=+4\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=4-2x\" Subtract \"2x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B4\" Rearrange the terms.\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\" through the points and \r
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\n" ); document.write( "\n" ); document.write( "Now let's graph the equation \"3x+-+4y+=+6\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x+-+4y+=+6\" Start with the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=6-3x\" Subtract \"3x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%286-3x%29%2F%28-4%29\" Divide both sides by \"-4\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=%286%29%2F%28-4%29-%283x%29%2F%28-4%29\" Break up the fraction.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3%2F2%2B%283x%29%2F%284%29\" Reduce \r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%2F4%29x-3%2F2\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"y=%283%2F4%29x-3%2F2\" we can see that the equation is in slope-intercept form \"y=mx%2Bb\" where the slope is \"m=3%2F4\" and the y-intercept is \"b=-3%2F2\" \r
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\n" ); document.write( "\n" ); document.write( "Since \"b=-3%2F2\" 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 \"3%2F4\", this means:\r
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\n" ); document.write( "\n" ); document.write( "\"rise%2Frun=3%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "which shows us that the rise is 3 and the run is 4. This means that to go from point to point, we can go up 3 and over 4\r
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\n" ); document.write( "\n" ); document.write( "So starting at , go up 3 units \r
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\n" ); document.write( "\n" ); document.write( "and to the right 4 units 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=%283%2F4%29x-3%2F2\"\r
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\n" ); document.write( "\n" ); document.write( " So this is the graph of \"y=%283%2F4%29x-3%2F2\" through the points and \r
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\n" ); document.write( "\n" ); document.write( "So together the two graphs look like \r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=-2x%2B4\" (red) and \"y=%283%2F4%29x-3%2F2\" (green)\r
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\n" ); document.write( "\n" ); document.write( "From the graph, we can see that the two lines intersect at the point (2,0). So the solution of the system is \"x=2\" and \"y=0\"
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