Question 388595
Plot the line {{{-x+y=-1}}}
{{{y=x-1}}}
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{{{graph(300,300,-10,10,-10,10,x-1)}}}
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*[invoke plot_any_inequality "-x+y<-1", -10, 10, -10, 10, 300, 300]
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Similarly, plot the line {{{x+y=1}}}
{{{y=-x+1}}}
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{{{graph(300,300,-10,10,-10,10,-x+1)}}}
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*[invoke plot_any_inequality "x+y>=1", -10, 10, -10, 10, 300, 300]
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{{{graph(300,300,-10,10,-10,10,x-1,-x+1)}}}
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Comparing the regions with the graphs plotted together, you would shade the region between the lines to the right of x=1. 
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