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4-2-31 compound inequality
X
    00:00 / 00:00
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    When looking at this problem, it's a compound inequality, IE there are three parts. Anything we do to one part, we have to do to all three parts. And our goal is to get X by itself, so we're going to multiply. Or we could think of it as dividing all three parts by a -1. If we multiply or divide all three parts by a -1, we have to flip all of the inequality signs and change any term that's negative to positive and positive to negative. Typically, we rewrite with the smaller number coming first, so we want all the X values that are in between -1 and three. So we're going to put an open dot at -1 because it wasn't or equal to, and we're going to put a closed dot at 3:00 because it was or equal to it was. X is less than or equal to three, so we're going to shade in between there. Now, there are a lot of different ways we could do this. We could think about this as two separate inequalities. If we prefer, we could say -3 less than or equal to negative X. And and it's an and because it's a compound inequality. I need these both to be true. Negative X less than one. If we multiply here, we'd get three greater than or equal to XI. Personally, like my X's to come first, so I would have X less than or equal to three if I multiply a -1 in the second piece. Now, because it's an and they both would have to be true, I need X less than or equal to three. So solid dot here shaded off to the left, X greater than -1 so an open dot here shaded off to the right. When I think about where they both true, they're both true in here -1, 3. They're both true at 3:00 but only one was true at that -1 hence I'm going to use a arenthesis there. Hope this helps.