WEBVTT
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Hi, what I'd like to show you guys how to evaluate an expression you do using order
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of operations.
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A lot of a very quick reminder for order of operations, hey I really like to use the
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help people do it as please excuse my hearing Sally.
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And what that pretty much means is this is kind of your order of operations, this is
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what you're going to do first.
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Now if you guys remember we have also been working so much with solid equations that we've
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always done the reverse order of operations because order of operations tell you always
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do what's inside the parentheses first, then to do your exponents, then you do your
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multiply divide and when you're doing your multiply divide make sure you do them from
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left to right.
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So it's not so much you have to do multiplication for you to do division, we just have to make
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sure you do the left multiplication first.
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And the same thing with addition and subtraction always work from left to right.
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So if I first look at this problem, I'm going to see that while I have brackets I have
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parentheses, brackets and math are going to have the same exact quality, they're going
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to do the exact same things are parentheses.
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So I first look inside, I'm not going to be concerned with this for because it's outside
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of my brackets.
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Then I'm going to go and look inside here and I have another set of parentheses and I
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know that this is going to be the first thing I'm going to do because this is the innermost
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parentheses.
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So therefore I'm going to do this operation first.
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So therefore I'm going to do 10 minus 2.
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So I'm just going to rewrite and just going to do this step by step.
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So you guys can see 30 minus 10 minus 2 becomes 8 and then times 2.
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Now I'm going to look at this and now I have a choice either to do subtraction or multiplication.
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Since I'm following the order of operations it's said to do multiplication first.
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Now you might say well subtractions to the left, it doesn't matter since multiplication
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division is first, that's what you're going to do on your order of operations, that's
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what you have to do first.
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So I do 4 times 30 minus 8 times 3 which is going to be 24.
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30 and then again I'm not going to find this for you because this 4 is outside the
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parentheses.
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So therefore I have 4 times 6 and then therefore that is going to give me 24.
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Okay, just a couple of last things to remind you.
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Make sure you always do inside the parentheses first and then you go and work on one's outside
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of the parentheses.
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Make sure you follow your multiplication, do always that first before you do your disinstraction
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and always work from left to right and remember that this is opposite of what we did for
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solid equations.
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When you're doing solid equations you do the first order of operations.
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Okay, so that's how you use value and expression using order of operations.