Solution - Linear equations with one unknown

Rearrange:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

                     -21-(-21-b)=0 

Step by step solution :

Step  1  :

Solving a Single Variable Equation :

 1.1      Solve  :    b = 0 

  Solution is  b = 0

One solution was found :