document.write( "Question 228672: graph x+2y=8 \n" ); document.write( "
Algebra.Com's Answer #169674 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Graphing Linear Equations

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\n" ); document.write( " \"1%2Ax%2B2%2Ay=8\"Start with the given equation
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\n" ); document.write( " \"2%2Ay=8-1%2Ax\" Subtract \"1%2Ax\" from both sides
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\n" ); document.write( " \"y=%281%2F2%29%288-1%2Ax%29\" Multiply both sides by \"1%2F2\"
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\n" ); document.write( " \"y=%281%2F2%29%288%29-%281%2F2%29%281%29x%29\" Distribute \"1%2F2\"
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\n" ); document.write( " \"y=8%2F2-%281%2F2%29x\" Multiply
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\n" ); document.write( " \"y=%28-1%2F2%29%2Ax%2B8%2F2\" Rearrange the terms
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\n" ); document.write( " \"y=%28-1%2F2%29%2Ax%2B4\" 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=4\" (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%2B4\"
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\n" ); document.write( " \"y=8%2F2%2B4\" Multiply
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\n" ); document.write( " \"y=16%2F2\" Add
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\n" ); document.write( " \"y=8\" Reduce
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\n" ); document.write( " So here's one point (-8,8)
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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%2B4\"
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\n" ); document.write( " \"y=6%2F2%2B4\" 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 another point (-6,7). 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%2B4\" through the points (-8,8) and (-6,7)
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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,\"4\")and the x-intercept is (\"8\",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=4\" this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,\"4\").
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\n" ); document.write( " So we have one point (0,\"4\")
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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,\"4\"), 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%2B4\"
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\n" ); document.write( " So this is the graph of \"y=%28-1%2F2%29%2Ax%2B4\" through the points (0,4) and (2,3)
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