i need help writing an equation for this question

An equation to represent the situation in the model :-
[tex]3x = 12[/tex]
Let us solve this equation and find the value of x .
So :-
[tex]3x = 12[/tex]
[tex]x = \frac{12}{3} [/tex]
[tex]x = 4[/tex]
Therefore , an equation to represent the model is 3x = 12 , and the value of x = 4 .