Solve for the Variable Involving Mixed Operations

We use inverse operations to solve the equation for a variable.
 

For example, consider the equation 4a – 7 = 33.

 

To find the value of a, first of all, add 7 to both the sides of the equation.
 

4a – 7 + 7 = 33 + 7    
 

4a = 40
 

Now, divide both sides by 4 to find the value of a.    

 

4a 4

=

40 4

  a = 10