Question

When graphing a linear inequality, when can you NOT use (0,0) as a test point to determine which side of a boundary line to shade?

Answer 1

You have to see if the boundary line is a continuous line or a dashed line. If the line is continuous then the answer you get should be included in the shaded area. If the line is dashed then the answer you get will not be in the shaded area. But if you have compare two inequalities then the overlapping shaded area should include both answers in the shaded area.