document.write( "Question 103016: Solve by graphing.
\n" ); document.write( "x-y=5
\n" ); document.write( "x+y=3
\n" ); document.write( "Am I the only person that does not get graphing?
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Algebra.Com's Answer #74912 by edjones(8007)\"\" \"About 
You can put this solution on YOUR website!
Study this information hard and you will become expert.
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Solved by pluggable solver: Graphing Linear Equations

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\n" ); document.write( " \"1%2Ax-1%2Ay=5\"Start with the given equation
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\n" ); document.write( " \"-1%2Ay=5-1%2Ax\" Subtract \"1%2Ax\" from both sides
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\n" ); document.write( " \"y=%28-1%29%285-1%2Ax%29\" Multiply both sides by \"-1\"
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\n" ); document.write( " \"y=%28-1%29%285%29%2B%281%29%281%29x%29\" Distribute \"-1\"
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\n" ); document.write( " \"y=-5%2B%281%29x\" Multiply
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\n" ); document.write( " \"y=1%2Ax-5\" Rearrange the terms
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\n" ); document.write( " \"y=1%2Ax-5\" 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=-5\" (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=-4
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\n" ); document.write( " \"y=1%2A%28-4%29-5\"
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\n" ); document.write( " \"y=-4-5\" Multiply
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\n" ); document.write( " \"y=-9\" Add
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\n" ); document.write( " So here's one point (-4,-9)
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\n" ); document.write( " Now lets find another point
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\n" ); document.write( " Plug in x=-3
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\n" ); document.write( " \"y=1%2A%28-3%29-5\"
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\n" ); document.write( " \"y=-3-5\" Multiply
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\n" ); document.write( " \"y=-8\" Add
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\n" ); document.write( " So here's another point (-3,-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-5\" through the points (-4,-9) and (-3,-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,\"-5\")and the x-intercept is (\"5\",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=-5\" this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,\"-5\").
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\n" ); document.write( " So we have one point (0,\"-5\")
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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,\"-5\"), 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-5\"
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\n" ); document.write( " So this is the graph of \"y=1%2Ax-5\" through the points (0,-5) and (1,-4)
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Solved by pluggable solver: Graphing Linear Equations

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\n" ); document.write( " \"1%2Ax%2B1%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=%281%29%283-1%2Ax%29\" Multiply both sides by \"1\"
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\n" ); document.write( " \"y=%281%29%283%29-%281%29%281%29x%29\" Distribute \"1\"
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\n" ); document.write( " \"y=3-%281%29x\" Multiply
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\n" ); document.write( " \"y=-1%2Ax%2B3\" Rearrange the terms
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\n" ); document.write( " \"y=-1%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\" (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%2B3\"
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\n" ); document.write( " \"y=6%2B3\" 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%2B3\"
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\n" ); document.write( " \"y=5%2B3\" 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%2B3\" 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 down -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 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%2B3\"
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\n" ); document.write( " So this is the graph of \"y=-1%2Ax%2B3\" through the points (0,3) and (1,2)
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Solved by pluggable solver: Solve the System of Equations by Graphing

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\n" ); document.write( " Start with the given system of equations:
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\n" ); document.write( " \"1x-y=5\"
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\n" ); document.write( " \"1x%2By=3\"
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\n" ); document.write( " In order to graph these equations, we need to solve for y for each equation.
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\n" ); document.write( " So let's solve for y on the first equation
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\n" ); document.write( " \"1x-y=5\" Start with the given equation
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\n" ); document.write( " \"-y=5-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"-y=-x%2B5\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x%2B5%29%2F%28-1%29\" Divide both sides by \"-1\"
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\n" ); document.write( " \"y=%28-1%2F-1%29x%2B%285%29%2F%28-1%29\" Break up the fraction
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\n" ); document.write( " \"y=x-5\" Reduce
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\n" ); document.write( " Now lets graph \"y=x-5\" (note: if you need help with graphing, check out this solver)
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\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+x-5%29+\" Graph of \"y=x-5\"
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\n" ); document.write( " So let's solve for y on the second equation
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\n" ); document.write( " \"1x%2By=3\" Start with the given equation
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\n" ); document.write( " \"1y=3-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"1y=-x%2B3\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x%2B3%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28-1%2F1%29x%2B%283%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=-x%2B3\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=-x%2B3\" to our first plot to get:
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\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+x-5%2C-x%2B3%29+\" Graph of \"y=x-5\"(red) and \"y=-x%2B3\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"4\",\"-1\") (note: you might have to adjust the window to see the intersection)

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