Answer:
Step 3, because a number has been added only to one side of the equation
Step-by-step explanation:
Here, the given equation is,
The steps for solving this equation would be,
Step 1 : Apply distributive property on left side of the equation,
Step 2 : Combine like terms in left side,
Step 3 : Add 2 on both sides ( additive property of equality ),
Step 4 : Combine like terms,
Step 5 : Isolate x,
Thus, by the above explanation it is clear that he did it mistake on step 3, ( he did not add 2 on right side of the equation ),
Hence, Third option is correct.