Solution - Linear equations with one unknown

Step by step solution :

Step  1  :

Pulling out like terms :

 1.1     Pull out like factors :

   -3x + 12  =   -3 • (x - 4) 

Equation at the end of step  1  :

Step  2  :

Equations which are never true :

 2.1      Solve :    -3   =  0

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

Solving a Single Variable Equation :

 2.2      Solve  :    x-4 = 0 

 Add  4  to both sides of the equation : 
                      x = 4

One solution was found :