Today I was working with a student on graphing inequalities. I noticed he was having a difficult time figuring out which way to shade the number line. A simple way to know is if the variable is written before the inequality sign, shade in the direction that the sign is pointing. For example, if the inequality x < 5, we have an open circle at 5 since 5 is not included in the solution and we shade to the left. If the inequality is x > 5, we would shade to the right since the point of the sign it to the right. Think of the sign as an arrow... ----------> or <-------------. In the example -2 < x < = 1 (< = means less than or euqal to) there it an open circle at -2, a closed circle at 1 and everything in between is shaded.

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