You can put this solution on YOUR website! Choose a value for x and then solve for y;
x+y<5
x=1
1+y =5
y=5-1=4
y=4
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x=0
0+y=5
y=5
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x=2
2+y=5
y=5-2=3
y=3
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Since it is y<5, the line is a dash line and you shade the area below the line.
:)
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