Question 685857
Graph:
x + y < 4
Solve for "y";
y < -x + 4
Graph the boundary line, y = -x+4, as a dashed line
Then shade the half-plane BELOW the boundary as 
you want y to be LESS than -x+4.
{{{graph(400,400,-10,10,-10,10,y < -x+4)}}}
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x - y > 4 
Solve for "y":
y < x -4
Boundary line y = x-4 as a dashed line.
Shade BELOW.
{{{graph(400,400,-10,10,-10,10,y < x-4)}}}
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Cheers,
Stan H.
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