It depends whether a variable is dependent or independent. In the video, he presents two scenarios: scenario 1: you want to buy a certain number of apples scenario 2: you have a limited budget. In the first scenario, the number of apples (a) is the independent variable, but in the second one it's the total cost (c) since _*you*_ decide how many apples or how much your budget is, the _dependent_ variable _depends_ on *your decision* of the independent variable. Here's another analogy, a dependent variable is like a passenger in a car, and an independent variable is like the driver. The driver (the independent variable) determines the car's direction and speed, while the passenger (the dependent variable) goes along for the ride. In the same way, the value of the dependent variable depends on the value of the independent variable.

Can someone tell me simply what an independent and dependent variables are and how they are different?

independent variables are called by other names such as input, domain, etc. and dependent variables are called by output, range, etc. So you have to start with something to put into an equation (independent) to be able to calculate something (output). When we are thinking more abstract, we generally use x for input and y for output. In Math and Science, you get equations that could shift inputs and outputs as needed. If you have A=bh, you could be given b and h as inputs to calculate A, or we could be given A and h to find b, so we would have to use b=A/h. Same thing would happen with h. We will often see the dependent variable isolated on one side by itself, but not always.

Does the independent come before the equal sign or after

It depends on which form of equations you are talking about. Often, many forms isolate the dependent variable (which usually ends up on the left side of the equation) such as y=mx+b (linear) or y=ax^2+bx+c (quadratic). Thus, in general the dependent is isolated on the left and the independent is on the right.

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Course: Pre-algebra > Unit 7

Lesson 8: Dependent and independent variables

Dependent & independent variables

Name: Dependent & independent variables
Uploaded: 2022-01-18T21:00:10.077579154Z
Description: We introduce independent and dependent variables: how to identify the independent/dependent variable in a given setting, and how we write equations with the dependent variable by itself.

Google Classroom

We introduce independent and dependent variables: how to identify the independent/dependent variable in a given setting, and how we write equations with the dependent variable by itself. Created by Sal Khan.

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2201375
Posted a year ago. Direct link to 2201375's post “This is confusing”
This is confusing
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- Ananta
  Posted a year ago. Direct link to Ananta's post “It depends whether a vari...”
  It depends whether a variable is dependent or independent. In the video, he presents two scenarios:
  
  scenario 1: you want to buy a certain number of apples
  scenario 2: you have a limited budget.
  
  In the first scenario, the number of apples (a) is the independent variable, but in the second one it's the total cost (c) since you decide how many apples or how much your budget is, the dependent variable depends on your decision of the independent variable.
  
  Here's another analogy, a dependent variable is like a passenger in a car, and an independent variable is like the driver. The driver (the independent variable) determines the car's direction and speed, while the passenger (the dependent variable) goes along for the ride. In the same way, the value of the dependent variable depends on the value of the independent variable.
  Comment on Ananta's post “It depends whether a vari...”
  (17 votes)
khoi.nguyen.0807
Posted a year ago. Direct link to khoi.nguyen.0807's post “I love apple”
I love apple
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- Jacob
  Posted 4 months ago. Direct link to Jacob's post “banana are cool..... yeah”
  banana are cool..... yeah
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CinderpeltAteMyName
Posted a year ago. Direct link to CinderpeltAteMyName's post “Can someone tell me simpl...”
Can someone tell me simply what an independent and dependent variables are and how they are different?
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(3 votes)
Answer
- David Severin
  Posted a year ago. Direct link to David Severin's post “independent variables are...”
  independent variables are called by other names such as input, domain, etc. and dependent variables are called by output, range, etc. So you have to start with something to put into an equation (independent) to be able to calculate something (output). When we are thinking more abstract, we generally use x for input and y for output.
  In Math and Science, you get equations that could shift inputs and outputs as needed. If you have A=bh, you could be given b and h as inputs to calculate A, or we could be given A and h to find b, so we would have to use b=A/h. Same thing would happen with h. We will often see the dependent variable isolated on one side by itself, but not always.
  Comment on David Severin's post “independent variables are...”
  (8 votes)
H3V1.
Posted 2 years ago. Direct link to H3V1.'s post “wait, if the independent ...”
wait, if the independent and dependent variables are interchangeable, how do we know which to label as which (idk if that made sense)?
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(4 votes)
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- joaopaulovf
  Posted 6 months ago. Direct link to joaopaulovf's post “The dependent and indepen...”
  The dependent and independent variables change according to how you make the equation. Generally, dependent variables stay alone on one side of the equation, while the independent ones are in an operation(sum, subtraction, multiplication, division and so on).
  
  Using the video example:
  
  c = 2a --> c is dependent and a is independent(because it is multiplied by 2)
  
  a = c/2 --> a is dependent and c is independent(because it is divided by 2)
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  (1 vote)
rubykate622
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bro this is soooo easy! but, the questions WE have to do are hard. not fair
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cain
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Is it just me who never pays attention to the videos?
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Elnemr, Amar
Posted 2 years ago. Direct link to Elnemr, Amar's post “Does the independent come...”
Does the independent come before the equal sign or after
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- David Severin
  Posted 2 years ago. Direct link to David Severin's post “It depends on which form ...”
  It depends on which form of equations you are talking about. Often, many forms isolate the dependent variable (which usually ends up on the left side of the equation) such as y=mx+b (linear) or y=ax^2+bx+c (quadratic). Thus, in general the dependent is isolated on the left and the independent is on the right.
  Button navigates to signup page
  (2 votes)
brayzten.niino
Posted a month ago. Direct link to brayzten.niino's post “how do we do this”
how do we do this
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miriam.tolstyka1
Posted a month ago. Direct link to miriam.tolstyka1's post “Can a variable be both de...”
Can a variable be both dependent and independent?
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Gremlin
Posted 9 months ago. Direct link to Gremlin's post “So, the dependent variabl...”
So, the dependent variable is what you are solving for? Is this always the case?
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Video transcript

- [Teacher] Let's say that you love to eat apples, and you are going to buy a apples, so a is the number of apples, number of apples, but you also have a budget, so you have to care about costs, so let's say C is equal to the total cost, and let's say that the price of an apple is $2, so $2 per apple. There's several ways that we can express the relationship between the total cost and the number of apples. One way is if we solve for the total cost, and we say, okay, the total cost is gonna be $2 per apple times the number of apples, so it's going to be 2a. Another way that we could rewrite this if we were to divide both sides of this by two, we would get that the number of apples is equal to cost over two. These are equivalent expressions I should say these are equivalent equations, but the way they've been written, make it useful for different scenarios. For example, on the left-hand side here, it's really easy to try out different As and then think about how that will affect the cost, and so when it's written like this, we would call the variable that it's easy to try out different values, we would call that the independent variable, independent variable, and then the one that we are essentially solving for that we then spit out a value after we compute using the independent variable, you call that the dependent variable. You could view it as, look in this situation, the cost is dependent on the number of apples you choose to eat. Now, when we wrote it over here, this looks a little bit different. Now the number of apples is solved for, and we compute how many apples based on the cost, so this would be a scenario where you have a budget and you tell me what the budget is and I could tell you the number of apples. So in this situation, C is the independent variable, and since we have solved for a, a is the dependent variable. This is useful if I give you a number of apples and you want to know the total cost, and this is useful if you have a certain cost and then you want to find out the number of apples.