document.write( "Question 114744: Graph by first solving for y.
\n" ); document.write( " x – 3y = 9
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Algebra.Com's Answer #83492 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-3%2Ay=9\"Start with the given equation
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\n" ); document.write( " \"-3%2Ay=9-1%2Ax\" Subtract \"1%2Ax\" from both sides
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\n" ); document.write( " \"y=%28-1%2F3%29%289-1%2Ax%29\" Multiply both sides by \"-1%2F3\"
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\n" ); document.write( " \"y=%28-1%2F3%29%289%29%2B%281%2F3%29%281%29x%29\" Distribute \"-1%2F3\"
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\n" ); document.write( " \"y=-9%2F3%2B%281%2F3%29x\" Multiply
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\n" ); document.write( " \"y=%281%2F3%29%2Ax-9%2F3\" Rearrange the terms
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\n" ); document.write( " \"y=%281%2F3%29%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%2F3\" (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=-9
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\n" ); document.write( " \"y=%281%2F3%29%2A%28-9%29-3\"
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\n" ); document.write( " \"y=-9%2F3-3\" Multiply
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\n" ); document.write( " \"y=-18%2F3\" Add
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\n" ); document.write( " \"y=-6\" Reduce
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\n" ); document.write( " So here's one point (-9,-6)
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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=%281%2F3%29%2A%28-6%29-3\"
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\n" ); document.write( " \"y=-6%2F3-3\" Multiply
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\n" ); document.write( " \"y=-15%2F3\" Add
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\n" ); document.write( " \"y=-5\" Reduce
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\n" ); document.write( " So here's another point (-6,-5). 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=%281%2F3%29%2Ax-3\" through the points (-9,-6) and (-6,-5)
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\n" ); document.write( " So from the graph we can see that the slope is \"1%2F3\" (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 3 units to get to the next point) the y-intercept is (0,\"-3\")and the x-intercept is (\"9\",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%2F3\", 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 3 units to get to our next point
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\n" ); document.write( " Now draw a line through those points to graph \"y=%281%2F3%29%2Ax-3\"
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\n" ); document.write( " So this is the graph of \"y=%281%2F3%29%2Ax-3\" through the points (0,-3) and (3,-2)
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