Answer:
x = 12
Step-by-step explanation:
Frida adds 3 to both the sides of the equation 3x = 36.
When we are to solve an equation we tend to simplify it and move towards arriving at a value for the variable.
When Frida adds 3 to both sides, it becomes 3x + 3 = 36 + 3
⇒ 3x + 3 = 39
This has complicated the equation. Instead Frida should have divided both the sides of the equation by 3. That would have resulted in x = 12 right away!.