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 :

                     42-(-7*(z-3))=0 

Step by step solution :

Step  1  :

Equation at the end of step  1  :

  42 -  (0 -  7 • (z - 3))  = 0 

Step  2  :

Step  3  :

Pulling out like terms :

 3.1     Pull out like factors :

   7z + 21  =   7 • (z + 3) 

Equation at the end of step  3  :

  7 • (z + 3)  = 0 

Step  4  :

Equations which are never true :

 4.1      Solve :    7   =  0

This equation has no solution.
A a non-zero constant never equals zero.

Solving a Single Variable Equation :

 4.2      Solve  :    z+3 = 0 

 Subtract  3  from both sides of the equation : 
                      z = -3

One solution was found :