Well, that's one correction made, yes. But what the other posters were trying to point out is that one of your signs is pointing the wrong way in case c. What you wrote doesn't at all say what you think it says. Think about what the two halves of the inequality are saying. [tex]-1 \le x[/tex] tells you that -1 is less than or equal to x. Or, in other words, x is greater than or equal to -1. All good so far, but now let's look at the second half. [tex]x \ge 2[/tex]. This says that x is greater than or equal to 2.

Putting those together, the whole inequality says that x is greater than to equal to -1, and x is greater than or equal to 2. Oops! What you wrote is technically accurate, but it's vacuously true. Given [tex]x \ge 2[/tex], it automatically follows that [tex]x \ge -1[/tex] by the property of transitivity (because [tex]2 \ge -1[/tex]). Also, aside from not representing the interval you desire, it's just poor, very confusing notation. If you were to punch that into a graphing calculator, like, say,

**Desmos**, it would throw up an error: "Double inequalities must both go the same way, e.g. [tex]1 \le y \le 2[/tex]."

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