WEBVTT
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Alright, what we're going to do now, oh that's a 5.5T isn't it?
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Alright, so what we do guys, we need to solve for T on this problem.
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Alright, now when solving for T on this problem, we have a big issue because we don't have one T.
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Alright, it's very easy when we have something like this.
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T plus 3 equals 4, right?
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Well we only had one T to solve for so we subtracted the 3 and we got T equals 1 and we were good, right?
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It was easy.
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Well now we have 3Ts, so what we need to do is we need to combine thoseTs down to 1.
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Now to even make combining like numbers harder, we have fractions now I'm used.
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So there's nothing wrong with adding 5.5T and then subtracting T from it and figuring that out.
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What you have to do is you have to change this to a fraction by multiplying 2 over 2, which 5.5 is minus 1.
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Alright, this doesn't have the same denominator, so you have to multiply by 2 over 2.
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So you get 5.5 minus 2 over 2, which equals 3.
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So if you guys remember the coefficient of T is 1, so we could do that.
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However, I don't want to deal with fractions right now.
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I don't know if there's my headache I got going on or what, but I'm not going to deal with fractions.
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So you guys can remember if you don't want to deal with fractions and you can't be a fraction operations, give rid of them.
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So the way we can get rid of fractions is look at our denominator.
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Alright, and if you have different denominators, then you're going to want to take the lowest multiple of those two denominators,
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what we call the least common multiple.
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And what we're going to do is we're going to divide every single number times our denominator or the least common multiple.
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So I'm going to multiply this by 2, this by 2, this by 2, and this is going to be 2.
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Okay, therefore these cancel out and those two cancel out because 2 divided by 2 gives you 1.
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Therefore I'm left with 5t minus 2t equals 6 plus 3t.
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Now it's much easier for me to combine like terms, right?
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Because fractions, nobody likes adding subtractive fractions.
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They have to do the common multiple.
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It just gets tedious.
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So here it's easy. 5t minus 2t, right?
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It's going to equal 3t.
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No pretty good, right?
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Guess what I did.
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I went down from 3t's, now I'm down to 2t's.
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Right?
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Now I need to get to my last t.
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So I need to subtract t on both sides.
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So I subtract the t here, and I subtract 3t over here.
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And what I get is 0 equals 6.
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Is 0 ever equal to 6?
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No.
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No.
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No.
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Now here's a problem.
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0 is never equal to 6, will it?
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So here's one way you guys can say.
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So this is what we call no solution.
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And the reason why this is no solution is if you guys look at this equation,
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what if I plugged in a number for t?
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Let's say I plugged in a number 2.
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If I plugged in a number 0, I get 0 equals 6, right?
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If I plugged in a number 1, I get 3 is equal to 9.
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So guess what?
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There's not a number we can use for t that these will ever be equal to each other,
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because look at it.
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No matter if I, whatever I've put in for t here,
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I have to put that same number for t here, right?
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But then on the right side, I'm always going to add 6.
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So these two are never going to equal each other.
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So therefore, this won't call no solution.
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But the main important thing I want to do is also show you guys how to cross out those fractions.
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Thank you.
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Thank you.
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Thank you.
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Thank you.