Using inverse operations to solve equations

 
 
Inverse operations.jpeg
 
 
 

Inverse operations undo each other

Inverse operations are operations that are opposite or “undo” each other.

For example, addition undoes subtraction and division undoes multiplication.

Inverse operations are useful when solving equations.

Krista King Math.jpg

Hi! I'm krista.

I create online courses to help you rock your math class. Read more.

 

Inverse operation examples:

Addition/Subtraction ???x+3-3=x???

Multiplication/Division ???x\cdot3\div3=x???

Exponents/Roots ???\sqrt{x^2}=x???

 
 

How to use inverse operations to solve equations


 
Krista King Math Signup.png
 
Algebra 1 course.png

Take the course

Want to learn more about Algebra 1? I have a step-by-step course for that. :)

 
 

 
 

To use an inverse operation, just do the opposite of what the equation says!

Example

Use inverse operations to complete the equation.

???2+7\quad?\quad=7???

In this example ???2??? is being added to ???7???, to undo that operation we need to subtract by ???2???.

???2+7-2=7???

Simplify to show that the equation is true.

???2-2+7=7???

???0+7=7???

???7=7???


Let’s try another example of inverse operations.


Inverse operations

Inverse operations are operations that are opposite or “undo” each other.

For example, addition undoes subtraction and division undoes multiplication.

Example

Use inverse operations to complete the equation.

???4\cdot3\quad?\quad=4???

In this example ???4??? is being multiplied by ???3???, to undo that operation we need to divide by ???3???.

???4\cdot3\div3=4???

Simplify to show that the equation is true.

???4\cdot1=4???

???4=4???

 
Krista King.png
 

Get access to the complete Algebra 1 course