document.write( "Question 715656: I have no idea how to solve this problem.
\n" ); document.write( "It says graph x+y<-1
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Algebra.Com's Answer #439565 by KMST(5328)\"\" \"About 
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To graph an inequality you first graph the boundary line, making it a solid line if the inequality sign includes \"or equal\", or a dashed lined, if it's just greater than, or just lesser than.
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\n" ); document.write( "For \"x%2By%3C-1\" you will graph \"x%2By=-1\" as a dashed line.
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\n" ); document.write( "After graphing the boundary line, you color (or shade) the side of the line that represents all the solutions to the inequality.
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\n" ); document.write( "You could solve for y, \"x%2By%3C-1\" --> \"y%3C-x-1\"
\n" ); document.write( "and color as solution all the points below the line \"y=-x-1\" ,
\n" ); document.write( "because for each x, the points below the line have a y value that is less that the y on the line.
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\n" ); document.write( "HOW TO GRAPH A LINE:
\n" ); document.write( "If you know two points on the line, you just plot those points and connect them with a straight line.
\n" ); document.write( "I see that the line with the equation \"x%2By=-1\" passes through points (0,-1) and (-1,0) because
\n" ); document.write( "\"x=0\" makes the equation \"y=-1\" indicating that (0,-1) is a point on the line, and
\n" ); document.write( "\"y=0\" makes the equation \"x=-1\" indicating that (-1,0) is a point on the line.
\n" ); document.write( "I can use those points to graph the line.
\n" ); document.write( "If you have the equation in the slope-intercept form, a in \"y=-x-1\" , you can use the y-intercept for one point, and the slope to go from one point to another.
\n" ); document.write( "The \"-1\" at the end of \"y=-x-1\" tells you that the y-intercept is \"-1\" ,
\n" ); document.write( "meaning that the line crosses the y-axis at point (0,-1).
\n" ); document.write( "The line \"y=-x-1\" has a slope of \"-1\" (the coefficient of \"x\" ).
\n" ); document.write( "A slope of \"-1\" means that as \"x\" increases by 1, \"y\" increases by \"-1\" (meaning that it decreases by 1.
\n" ); document.write( "So from (0,-1) you would go to (1,-2) and then to (2,-3), and so on.
\n" ); document.write( "Reversing direction, you could go from (0,-1) to (-1,0) and then to (-2,1), and so on.
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\n" ); document.write( "HOW TO DECIDE WHICH SIDE OF THE LINE IS THE SOLUTION:
\n" ); document.write( "If your inequality is \"y%3C-x-1\" the lesser than sign tells you that the solution is all the points below the line with equation \"y=-x-1\"
\n" ); document.write( "If your inequality is something like \"x%2By%3C-1\" , you can figure out which side is the solution by using a test point that is not on the line.
\n" ); document.write( "You would chose a test point that makes calculations easy.
\n" ); document.write( "For \"x%2By%3C-1\", I would chose point (0,0), the origin.
\n" ); document.write( "Substituting \"x=0\" and \"y=0\" , I see that the origin is not part of the solution because
\n" ); document.write( "\"x%2By=0%2B0=0\" and \"0\" is not lesser than \"-1\".
\n" ); document.write( "So I know that the solution is the side of line that does not contain the origin.
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\n" ); document.write( "YOUR SOLUTION
\n" ); document.write( "is the green shaded area, all the way to the dashed blue line. but not including that line. (We draw the boundary line as a dashed line to show that the points of that line are not part of the solution).
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