document.write( "Question 114025: x + y = 8 \n" ); document.write( "
Algebra.Com's Answer #82976 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Do you want to graph this?\r
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Solved by pluggable solver: Graphing Linear Equations

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\n" ); document.write( " \"1%2Ax%2B1%2Ay=8\"Start with the given equation
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\n" ); document.write( " \"1%2Ay=8-1%2Ax\" Subtract \"1%2Ax\" from both sides
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\n" ); document.write( " \"y=%281%29%288-1%2Ax%29\" Multiply both sides by \"1\"
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\n" ); document.write( " \"y=%281%29%288%29-%281%29%281%29x%29\" Distribute \"1\"
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\n" ); document.write( " \"y=8-%281%29x\" Multiply
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\n" ); document.write( " \"y=-1%2Ax%2B8\" Rearrange the terms
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\n" ); document.write( " \"y=-1%2Ax%2B8\" 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=8\" (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=-1
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\n" ); document.write( " \"y=-1%2A%28-1%29%2B8\"
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\n" ); document.write( " \"y=1%2B8\" Multiply
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\n" ); document.write( " \"y=9\" Add
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\n" ); document.write( " So here's one point (-1,9)
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\n" ); document.write( " Now lets find another point
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\n" ); document.write( " Plug in x=0
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\n" ); document.write( " \"y=-1%2A%280%29%2B8\"
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\n" ); document.write( " \"y=0%2B8\" Multiply
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\n" ); document.write( " \"y=8\" Add
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\n" ); document.write( " So here's another point (0,8). 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%2B8\" through the points (-1,9) and (0,8)
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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 down -1 units and to the right 1 units to get to the next point), the y-intercept is (0,\"8\")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=8\" this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,\"8\").
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\n" ); document.write( " So we have one point (0,\"8\")
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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,\"8\"), we can go down 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%2B8\"
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\n" ); document.write( " So this is the graph of \"y=-1%2Ax%2B8\" through the points (0,8) and (1,7)
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