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UNDOING OPERATIONS

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SO, HOW DO WE UNDO OPERATIONS?

First we need to understand what all of the operations that we will be undoing are.

So, the operations are:

  1. Addition
  2. Subtraction
  3. Multiplication
  4. Division

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So, how do we undo Addition?

By subtracting. Whenever you see a + sign and you want to undo it, you subtract whatever is being added.

An example of this:

0 = x + 23

If we want to know what x is, we undo the addition.

So we subtract 23 from the equation.

-23 -23

And we get that x = -23

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Some Examples For undoing addition

  1. x + 12 = 36

  • 12 + x = 7

  • 5 + x = 12

4. x + 100 = 101

-12 -12

x = 24

-12 -12

x = -5

-5 -5

x = 7

-100 -100

x = 1

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So how do we undo Subtraction?

With addition! Whenever you see a - sign and you want to undo it, you add whatever is being subtracted.

An example of this:

x – 20 = 35

If we want to know what x is, we undo the subtraction.

So we add 20 from the equation.

+ 20 + 20

And we get that x = 55

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SOME EXAMPLES FOR UNDOING SUBTRACTION

  1. x - 24 = 27

  • x - 50 = 3

  • x – 47 = 2

  • -57 + x = 100

+24 +24

x = 51

+ 50 +50

x = 53

+ 47 +47

x = 49

+57 + 57

x = 157