Answer:

Option 2 and 3 is correct.
Step-by-step explanation:
Case (I).
Given equation is

Firstly, we will add of 7 in both sides

Now, same variable of opposite sign is cancelled

Now, taking 5 common from left side

Case (II).
Given equation

Firstly, we will add of 7 in both sides

Now, we will add of 20 in both sides

Now, taking common of 5 from left side

So, The next step on solving completing square is
and 