document.write( "Question 83028: Solve the following system of linear inequalities by graphing.
\n" ); document.write( "x – y < 3
\n" ); document.write( "x + 2y >6
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Algebra.Com's Answer #59584 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Lets graph the equations first\r
\n" ); document.write( "\n" ); document.write( "\"x-y=3\" Simply replace the inequality sign with an equal sign
\n" ); document.write( "\"x%2B2y=6\"\r
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\n" ); document.write( "\n" ); document.write( "So lets graph \"x-y=3\" first\r
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Solved by pluggable solver: Graphing Linear Equations

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\n" ); document.write( " \"1%2Ax-1%2Ay=3\"Start with the given equation
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\n" ); document.write( " \"-1%2Ay=3-1%2Ax\" Subtract \"1%2Ax\" from both sides
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\n" ); document.write( " \"y=%28-1%29%283-1%2Ax%29\" Multiply both sides by \"-1\"
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\n" ); document.write( " \"y=%28-1%29%283%29%2B%281%29%281%29x%29\" Distribute \"-1\"
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\n" ); document.write( " \"y=-3%2B%281%29x\" Multiply
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\n" ); document.write( " \"y=1%2Ax-3\" Rearrange the terms
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\n" ); document.write( " \"y=1%2Ax-3\" Reduce any fractions
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\n" ); document.write( " So the equation is now in slope-intercept form (\"y=mx%2Bb\") where \"m=1\" (the slope) and \"b=-3\" (the y-intercept)
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\n" ); document.write( " So to graph this equation lets plug in some points
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\n" ); document.write( " Plug in x=-6
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\n" ); document.write( " \"y=1%2A%28-6%29-3\"
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\n" ); document.write( " \"y=-6-3\" Multiply
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\n" ); document.write( " \"y=-9\" Add
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\n" ); document.write( " So here's one point (-6,-9)
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\n" ); document.write( " Now lets find another point
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\n" ); document.write( " Plug in x=-5
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\n" ); document.write( " \"y=1%2A%28-5%29-3\"
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\n" ); document.write( " \"y=-5-3\" Multiply
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\n" ); document.write( " \"y=-8\" Add
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\n" ); document.write( " So here's another point (-5,-8). Add this to our graph
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\n" ); document.write( " Now draw a line through these points
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\n" ); document.write( " So this is the graph of \"y=1%2Ax-3\" through the points (-6,-9) and (-5,-8)
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\n" ); document.write( " So from the graph we can see that the slope is \"1%2F1\" (which tells us that in order to go from point to point we have to start at one point and go up 1 units and to the right 1 units to get to the next point) the y-intercept is (0,\"-3\")and the x-intercept is (\"3\",0) . So all of this information verifies our graph.
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\n" ); document.write( " We could graph this equation another way. Since \"b=-3\" this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,\"-3\").
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\n" ); document.write( " So we have one point (0,\"-3\")
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\n" ); document.write( " Now since the slope is \"1%2F1\", this means that in order to go from point to point we can use the slope to do so. So starting at (0,\"-3\"), we can go up 1 units
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\n" ); document.write( " and to the right 1 units to get to our next point
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\n" ); document.write( " Now draw a line through those points to graph \"y=1%2Ax-3\"
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\n" ); document.write( " So this is the graph of \"y=1%2Ax-3\" through the points (0,-3) and (1,-2)
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\n" ); document.write( "\n" ); document.write( "Now lets graph \"x%2B2y=6\" \r
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Solved by pluggable solver: Graphing Linear Equations

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\n" ); document.write( " \"1%2Ax%2B2%2Ay=6\"Start with the given equation
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\n" ); document.write( " \"2%2Ay=6-1%2Ax\" Subtract \"1%2Ax\" from both sides
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\n" ); document.write( " \"y=%281%2F2%29%286-1%2Ax%29\" Multiply both sides by \"1%2F2\"
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\n" ); document.write( " \"y=%281%2F2%29%286%29-%281%2F2%29%281%29x%29\" Distribute \"1%2F2\"
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\n" ); document.write( " \"y=6%2F2-%281%2F2%29x\" Multiply
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\n" ); document.write( " \"y=%28-1%2F2%29%2Ax%2B6%2F2\" Rearrange the terms
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\n" ); document.write( " \"y=%28-1%2F2%29%2Ax%2B3\" Reduce any fractions
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\n" ); document.write( " So the equation is now in slope-intercept form (\"y=mx%2Bb\") where \"m=-1%2F2\" (the slope) and \"b=3\" (the y-intercept)
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\n" ); document.write( " So to graph this equation lets plug in some points
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\n" ); document.write( " Plug in x=-8
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\n" ); document.write( " \"y=%28-1%2F2%29%2A%28-8%29%2B3\"
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\n" ); document.write( " \"y=8%2F2%2B3\" Multiply
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\n" ); document.write( " \"y=14%2F2\" Add
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\n" ); document.write( " \"y=7\" Reduce
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\n" ); document.write( " So here's one point (-8,7)
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\n" ); document.write( " Now lets find another point
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\n" ); document.write( " Plug in x=-6
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\n" ); document.write( " \"y=%28-1%2F2%29%2A%28-6%29%2B3\"
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\n" ); document.write( " \"y=6%2F2%2B3\" Multiply
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\n" ); document.write( " \"y=12%2F2\" Add
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\n" ); document.write( " \"y=6\" Reduce
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\n" ); document.write( " So here's another point (-6,6). Add this to our graph
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\n" ); document.write( " Now draw a line through these points
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\n" ); document.write( " So this is the graph of \"y=%28-1%2F2%29%2Ax%2B3\" through the points (-8,7) and (-6,6)
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\n" ); document.write( " So from the graph we can see that the slope is \"-1%2F2\" (which tells us that in order to go from point to point we have to start at one point and go down -1 units and to the right 2 units to get to the next point), the y-intercept is (0,\"3\")and the x-intercept is (\"6\",0) . So all of this information verifies our graph.
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\n" ); document.write( " We could graph this equation another way. Since \"b=3\" this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,\"3\").
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\n" ); document.write( " So we have one point (0,\"3\")
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\n" ); document.write( " Now since the slope is \"-1%2F2\", this means that in order to go from point to point we can use the slope to do so. So starting at (0,\"3\"), we can go down 1 units
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\n" ); document.write( " and to the right 2 units to get to our next point
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\n" ); document.write( " Now draw a line through those points to graph \"y=%28-1%2F2%29%2Ax%2B3\"
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\n" ); document.write( " So this is the graph of \"y=%28-1%2F2%29%2Ax%2B3\" through the points (0,3) and (2,2)
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\n" ); document.write( "\n" ); document.write( "So lets graph \"y=x-3\" and \"y=%28-1%2F2%29x%2B3\" together\r
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\n" ); document.write( "\n" ); document.write( "Now lets pick the test point (0,0) and evaluate \"x-y%3C3\"\r
\n" ); document.write( "\n" ); document.write( "\"%280%29-%280%29%3C3\"\r
\n" ); document.write( "\n" ); document.write( "\"0%3C3\" true. Shade the region that does contain (0,0) for \"x-y=3\". So this means you shade above the line \"y=x-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"Photo\r
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\n" ); document.write( "\n" ); document.write( "Now lets use the same test point (0,0) and evaluate \"x%2B2y%3E6\"\r
\n" ); document.write( "\n" ); document.write( "\"%280%29%2B2%280%29%3E6\"\r
\n" ); document.write( "\n" ); document.write( "\"0%3E6\" false. Shade the region that doesn't contain (0,0) for \"x%2B2y=6\". So this means you shade above the line \"y=%28-1%2F2%29x%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "\"Photo\r
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\n" ); document.write( "\n" ); document.write( "Now the overlapping regions is the complete shading. In other words, every point that satisfies
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\n" ); document.write( "\"x-y%3C3\"
\n" ); document.write( "\"x%2B2y%3E6\"\r
\n" ); document.write( "\n" ); document.write( "is in this region. So this is what the overlapped shaded region looks like:\r
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\n" ); document.write( "\n" ); document.write( "\"Photo\r
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