WEBVTT
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All right, um, solve this using gallops combination
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. Right. So, um, one way in
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which did try Thio do these problems is it's very
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like, crank it out sort of way. What
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you do is just pick a variable and make all
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all the equations have the same coefficient for that.
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So prints on this one, I could take the
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exes, and I can change five for negative one
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. They all go into 20. All right,
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So I'm gonna make first this second and the third
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equation all start with 20 X. All right,
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so this equation gets multiplied by four. This equation
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gets multiplied by negative five. This equation gets multiplied
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by 20. Okay, um, now it's copy
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down the result of that. So the top equation
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becomes 20 acts minus 12. What? Plus 16
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z equals negative. Four cases, four times each
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of the terms. Negative. Five times a second
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. Equation 20 x. Yeah, I'm negative.
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Five times. Tubes. Why? And then Positive
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. 15. Not a legal 0500 The last one
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negative. One times. Bigger twins, 20 x
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. You're minus 100 watt minus 1 40 c equals
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a positive. Teach one. All right. And
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So now I have that I can combine these.
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So what I'm gonna do is I'm on this track
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. We're here, tracked them, and I think
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I'll subtract them. You a second equation, meister
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, Percy. It's a 20 mile 20 miles.
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20 0 Um, negative. 10 minus negative.
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Well, it's positive too. Why? And then
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15 minus 16 ISS negative one. See? And
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then zero. Minus negative for posit. Yeah.
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Now I'm gonna do the same thing with 2nd 2
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equations. 20 minus 20 homeless. Attract them.
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Me. See, I think they'll subtract these down
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the second equation. Minds for separation. So again
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, I have no access. Negative. 10 minus
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negative. 100. It's 90 and then 15 minus
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negative. 14 is 155. See? Equals two
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twin. Right? And so for this one now
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I want you Is by this equation, hours here
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, most by this equation by five make the wise
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both be 97 90. Why, um, minus
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45. See? Equals money up 90 times two
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. So there it's a track. Please bridge in
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something. Subtract them down. Euro ones for closet
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War one. How do we got here? Just
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double check this thing. This is right. Um
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, so that is 90 55 zero. 00 minus
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2 20 It's negative. All right, Better.
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Okay, so, um, spoke through. We
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have, uh, since he will subtract those,
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it's a tracked them down. So 90 Mind signing
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01 55 minus negative. 45 is 200 z equals
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negative. 20 minus one eighties negative. 400 Bible
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size by 200 z. Negative, too. Yeah
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. Yeah. Nice. Remember? So now I
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need to go back and find out what other variables
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are. So let's use this equation to find why
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, and so I get to Why minus see needles
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for so too. Why Bus too. Vehicles for
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And two, Why equals two and watch what?
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So no X and y Last thing to do is
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defined. See, I could take any of my
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way. I mean, I'm sorry to find X
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. Um, some of his last operation. It
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is just as a negative accident. So negative x
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plus five times. Why? Just one plus seven
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mimzy, which is negative too together equals negative.
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11. All right, so we get negative,
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X. Um, plus five minus 14 equals negative
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. 11. You'd be so native X. Um
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, this night, 11 and nine to both sides
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and negative. That's equal at 92 So that means
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X equals two. Um, and my order Triple
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B two one. You too, right?