why on earth is a picture of the queen of england in this video?

Hi Tianna! Great question! I think the reason for the Queen of England is because Sal just thought "NO" to logic Hope this helps =)

How do I setup an equation like 44-q=11 It's simply a true/false answer in my pre-algebra book. The answer is simple, it's 33. However, I don't know how to setup the equation. The example in the video shows the variable minus the number equals the difference. But what about when the number is first and the variable is subtracted from the number? How can I set up this equation so that future equations that cannot simply be solved without showing work can be solved?

Hey try to do this if you get 44-q=11 it you have to set it up like this at 0:15 he set it up like this that x+7=10. but one thing you have to remember is that if you have addition then you subtract and if you have subtraction than you have to add. in the x plus seven is equal to ten then you have to make a zero pair out of 7 so it equals to x and then you have to make the scale balance whatever you do the left side you have to on the right and subtract 10-7 which equals to 3 so you have to double like sal did in the first problem so he said this" 3+7 is indeed equal to 10.

May the queen rest in peace. Rest In Peace Queen Elizabeth the second.😇 Also how could they be paying respects to the Queen if this was made ten years ago way before she died. Yes, I looked on youtube and it said ten years ago.

it was her birthday when he uploaded it to YouTube all those years ago.

Why is the 5 considered to be a 'negative'? The way I read the equation, isn't it A, minus a positive number (n this case, 5)? And yet, Sal treats it as a negative number when balancing the equation. If it was supposed to be negative, should it not have read a - (-5) = -2?

The thing with negatives, is that the dash in front of it is a minus sign. If it is a positive number, there is actually a plus sign in front of it, but we don't use it (but it's still there). This also happens with the negative. It's a minus sign. I understand why you thought it was a positive (I thought it was positive as well before). The equation is `a - 5 = -2`. Treat the equation like this: `a + (-5) = -2`. They are still the same. Again, it's one of those things that are unspoken but still there, there is an addition sign there. If it was `a - (-5) = -2` as you stated, then it would simplify into `a + 5 = -2` which in turn means that `a = -7`. That was the time when my teacher taught me that the operator goes with the number or term after it. So logically, if you reordered -5 to be in front of a, you would get `-5 + a = -2` which still gives the same answer. Post a comment if you misunderstand something, I'll be glad to help. :-)

when your answering questions for khan academy, how do you answer 10 in a row when there's only 8 questions?

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Main content

6th grade

Course: 6th grade > Unit 7

Lesson 3: One-step addition & subtraction equations

One-step addition & subtraction equations

Name: One-step addition & subtraction equations
Uploaded: 2012-09-11T20:47:28Z
Description: In this lesson, we learn how to solve simple equations with one unknown variable. To find the unknown, we remove extra numbers by doing the opposite operation on both sides of the equation. This keeps the equation balanced and helps us find the value of the unknown variable.

Google Classroom

In this lesson, we learn how to solve simple equations with one unknown variable. To find the unknown, we remove extra numbers by doing the opposite operation on both sides of the equation. This keeps the equation balanced and helps us find the value of the unknown variable. Created by Sal Khan.

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Tianna
Posted 3 years ago. Direct link to Tianna's post “why on earth is a picture...”
why on earth is a picture of the queen of england in this video?
Button navigates to signup pageComment on Tianna's post “why on earth is a picture...”
(129 votes)
Answer
- aschuenke
  Posted 3 years ago. Direct link to aschuenke's post “Hi Tianna! Great questio...”
  Hi Tianna!
  
  Great question! I think the reason for the Queen of England is because Sal just thought "NO" to logic
  
  Hope this helps =)
  Comment on aschuenke's post “Hi Tianna! Great questio...”
  (50 votes)
Joel Robison
Posted 11 years ago. Direct link to Joel Robison's post “How do I setup an equatio...”
How do I setup an equation like 44-q=11 It's simply a true/false answer in my pre-algebra book. The answer is simple, it's 33. However, I don't know how to setup the equation. The example in the video shows the variable minus the number equals the difference. But what about when the number is first and the variable is subtracted from the number? How can I set up this equation so that future equations that cannot simply be solved without showing work can be solved?
Button navigates to signup pageComment on Joel Robison's post “How do I setup an equatio...”
(94 votes)
Answer
- Deven
  Posted 10 years ago. Direct link to Deven's post “Hey try to do this if you...”
  Hey try to do this if you get 44-q=11 it you have to set it up like this at
  0:15
  he set it up like this that x+7=10. but one thing you have to remember is that if you have addition then you subtract and if you have subtraction than you have to add. in the x plus seven is equal to ten then you have to make a zero pair out of 7 so it equals to x and then you have to make the scale balance whatever you do the left side you have to on the right and subtract 10-7 which equals to 3 so you have to double like sal did in the first problem so he said this" 3+7 is indeed equal to 10.
  Button navigates to signup page
  (10 votes)
SAHANASHR5
Posted 3 years ago. Direct link to SAHANASHR5's post “What is the Queen Elizabe...”
What is the Queen Elizabeth picture for?
Button navigates to signup pageComment on SAHANASHR5's post “What is the Queen Elizabe...”
(24 votes)
Answer
- michb20565
  Posted a year ago. Direct link to michb20565's post “Its cause she died 2 week...”
  Its cause she died 2 weeks ago
  Comment on michb20565's post “Its cause she died 2 week...”
  (2 votes)
Hailee Smith
Posted 3 years ago. Direct link to Hailee Smith's post “Why is queen elizabeth te...”
Why is queen elizabeth teaching me math
Button navigates to signup pageComment on Hailee Smith's post “Why is queen elizabeth te...”
(31 votes)
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- angel
  Posted a year ago. Direct link to angel's post “she is the smartest”
  she is the smartest
  Comment on angel's post “she is the smartest”
  (5 votes)
sophia.gorton
Posted 6 months ago. Direct link to sophia.gorton's post “May the queen rest in pea...”
May the queen rest in peace.
Rest In Peace Queen Elizabeth the second.😇
Also how could they be paying respects to the Queen if this was made ten years ago way before she died. Yes, I looked on youtube and it said ten years ago.
Button navigates to signup pageComment on sophia.gorton's post “May the queen rest in pea...”
(17 votes)
Answer
- sable/kade
  Posted 6 months ago. Direct link to sable/kade's post “it was her birthday when ...”
  it was her birthday when he uploaded it to YouTube all those years ago.
  Comment on sable/kade's post “it was her birthday when ...”
  (23 votes)
x.asper
Posted 3 years ago. Direct link to x.asper's post “Can someone please tell m...”
Can someone please tell me why the queen is in the video? It's hilarious and it pushes me on. It's like she is saying, "Do your algebra by the order of the queen!". I'm just laughing inside.
Comment on x.asper's post “Can someone please tell m...”
(27 votes)
Answer
Craig Jackson
Posted 8 years ago. Direct link to Craig Jackson's post “Why is the 5 considered t...”
Why is the 5 considered to be a 'negative'? The way I read the equation, isn't it A, minus a positive number (n this case, 5)? And yet, Sal treats it as a negative number when balancing the equation. If it was supposed to be negative, should it not have read a - (-5) = -2?
Button navigates to signup pageButton navigates to signup page
(17 votes)
Answer
- Johnathan
  Posted 8 years ago. Direct link to Johnathan's post “The thing with negatives,...”
  The thing with negatives, is that the dash in front of it is a minus sign. If it is a positive number, there is actually a plus sign in front of it, but we don't use it (but it's still there). This also happens with the negative. It's a minus sign.
  
  I understand why you thought it was a positive (I thought it was positive as well before).
  
  The equation is a - 5 = -2. Treat the equation like this: a + (-5) = -2. They are still the same. Again, it's one of those things that are unspoken but still there, there is an addition sign there. If it was a - (-5) = -2 as you stated, then it would simplify into a + 5 = -2 which in turn means that a = -7. That was the time when my teacher taught me that the operator goes with the number or term after it. So logically, if you reordered -5 to be in front of a, you would get -5 + a = -2 which still gives the same answer.
  
  Post a comment if you misunderstand something, I'll be glad to help. :-)
  Button navigates to signup page
  (16 votes)
Adam Herbst
Posted 4 months ago. Direct link to Adam Herbst's post “God save the Queen”
God save the Queen
Button navigates to signup pageComment on Adam Herbst's post “God save the Queen”
(16 votes)
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- JAKEF
  Posted 9 days ago. Direct link to JAKEF's post “british people”
  british people
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  (2 votes)
Austin Smith
Posted 7 months ago. Direct link to Austin Smith's post “Why is Queen Elizabeth in...”
Why is Queen Elizabeth in the background for the whole video
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(18 votes)
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- Subnauticaplayer88
  Posted 6 months ago. Direct link to Subnauticaplayer88's post “Probably paying respects”
  Probably paying respects
  Comment on Subnauticaplayer88's post “Probably paying respects”
  (0 votes)
ACKERPHO000
Posted 10 years ago. Direct link to ACKERPHO000's post “when your answering quest...”
when your answering questions for khan academy, how do you answer 10 in a row when there's
only 8 questions?
Button navigates to signup pageComment on ACKERPHO000's post “when your answering quest...”
(9 votes)
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- Anthony Jacquez
  Posted 10 years ago. Direct link to Anthony Jacquez's post “You can go to the video s...”
  You can go to the video section of Khan Academy and do the same skill twice equaling ten questions correct and earn the badge.
  Button navigates to signup page
  (11 votes)

Video transcript

Now that we're comfortable with the "why" of why we do something to both sides of an equation, let's see if we can apply it to some equations to solve for an unknown variable. So let's say that you have x plus seven is equal to ten, and I want to solve for x. All its saying is something plus seven is equal to ten, and you might be able to figure that out in your head, but if you want to do it a little bit more systematically, you're like well just all I want on the left hand side is an x. Well if all I want on the left hand side is an x I'd want to get rid of the seven. I want to subtract seven from the left-hand side, but if I want to maintain an equality here, whatever I do to the left-hand side I also have to do to the right-hand side going back to our scales that's so that we can keep our scale balanced, so that we can say that the left is still equal to the right. And so what we're going to be left with is x and then the sevens cancel out is equal to ten minus seven is equal to three. So that unknown is three, and you can verify it, three plus seven is indeed equal to ten. Let's try one more. Let's say we have a minus five is equal to negative two. So this is a little bit more interesting since we have all of these negative numbers here, but we can use the exact same logic. We just want an a over here on the left-hand side so we have to get rid of this negative five somehow. Well the best way of getting rid of a negative 5 is to add five to it. So I'll do that. So I will add five to the left-hand side. But if I want the left-hand side to stay equal to the right-hand side, whatever I do to the left I have to do the right. So I'm going to have to add five on the right-hand side as well, and so on the left-hand side I'm left with a, and then the negative five and the positive five cancel out and on the right hand side, and they're going to stay equal because I did the same thing to both sides, we have negative two plus five which is equal to three. So a is equal to three. Once again you can verify it. Three minus five is indeed equal to negative two.