document.write( "Question 199610This question is from textbook intermediate algebra
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\n" ); document.write( "\n" ); document.write( "i am trying to figure out how to find the x,y,xy corrdinates so i can graph the equation to find out this problem has one solution, no solution, or infininate solutions
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Algebra.Com's Answer #150002 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%283x-y=-3%2C2x%2By=-7%29\"\r
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\n" ); document.write( "\n" ); document.write( "In order to graph these equations, we must solve for y first.\r
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\n" ); document.write( "\n" ); document.write( "Let's graph the first equation:\r
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\n" ); document.write( "\n" ); document.write( "\"3x-y=-3\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-3-3x\" Subtract \"3x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-3-3x%29%2F%28-1%29\" Divide both sides by \"-1\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=3x%2B3\" Rearrange the terms and simplify.\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"y=3x%2B3\" we can see that the equation is in slope-intercept form \"y=mx%2Bb\" where the slope is \"m=3\" and the y-intercept is \"b=3\" \r
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\n" ); document.write( "\n" ); document.write( "Since \"b=3\" this tells us that the y-intercept is .Remember the y-intercept is the point where the graph intersects with the y-axis\r
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\n" ); document.write( "\n" ); document.write( "So we have one point \r
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\n" ); document.write( "\n" ); document.write( "Now since the slope is comprised of the \"rise\" over the \"run\" this means\r
\n" ); document.write( "\n" ); document.write( "\"slope=rise%2Frun\"\r
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\n" ); document.write( "\n" ); document.write( "Also, because the slope is \"3\", this means:\r
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\n" ); document.write( "\n" ); document.write( "\"rise%2Frun=3%2F1\"\r
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\n" ); document.write( "\n" ); document.write( "which shows us that the rise is 3 and the run is 1. This means that to go from point to point, we can go up 3 and over 1\r
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\n" ); document.write( "\n" ); document.write( "So starting at , go up 3 units \r
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\n" ); document.write( "\n" ); document.write( "and to the right 1 unit to get to the next point \r
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\n" ); document.write( "\n" ); document.write( "Now draw a line through these points to graph \"y=3x%2B3\"\r
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\n" ); document.write( "\n" ); document.write( " So this is the graph of \"y=3x%2B3\" through the points and \r
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\n" ); document.write( "\n" ); document.write( "Now let's graph the second equation:\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2By=-7\" Start with the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-7-2x\" Subtract \"2x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x-7\" Rearrange the terms and simplify.\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"y=-2x-7\" we can see that the equation is in slope-intercept form \"y=mx%2Bb\" where the slope is \"m=-2\" and the y-intercept is \"b=-7\" \r
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\n" ); document.write( "\n" ); document.write( "Since \"b=-7\" this tells us that the y-intercept is .Remember the y-intercept is the point where the graph intersects with the y-axis\r
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\n" ); document.write( "\n" ); document.write( "So we have one point \r
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\n" ); document.write( "\n" ); document.write( "\r
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\n" ); document.write( "\n" ); document.write( "Now since the slope is comprised of the \"rise\" over the \"run\" this means\r
\n" ); document.write( "\n" ); document.write( "\"slope=rise%2Frun\"\r
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\n" ); document.write( "\n" ); document.write( "Also, because the slope is \"-2\", this means:\r
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\n" ); document.write( "\n" ); document.write( "\"rise%2Frun=-2%2F1\"\r
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\n" ); document.write( "\n" ); document.write( "which shows us that the rise is -2 and the run is 1. This means that to go from point to point, we can go down 2 and over 1\r
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\n" ); document.write( "\n" ); document.write( "So starting at , go down 2 units \r
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\n" ); document.write( "\n" ); document.write( "and to the right 1 unit to get to the next point \r
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\n" ); document.write( "\n" ); document.write( "Now draw a line through these points to graph \"y=-2x-7\"\r
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\n" ); document.write( "\n" ); document.write( " So this is the graph of \"y=-2x-7\" through the points and \r
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\n" ); document.write( "\n" ); document.write( "Now let's graph the two equations together:\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=3x%2B3\" (red). Graph of \"y=-2x-7\" (green)\r
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\n" ); document.write( "\n" ); document.write( "From the graph, we can see that the two lines intersect at the point . So the solution to the system of equations is . \r
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\n" ); document.write( "\n" ); document.write( "This means that the system has one unique solution.\r
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\n" ); document.write( "\n" ); document.write( "This also tells us that the system of equations is consistent and independent.
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