For this case we have the following expression:

Applying distributive property to the terms within parentheses we have:

We add similar terms on both sides of equality considering that:
Equal signs are added and the same sign is placed.
Different signs are subtracted and the major sign is placed.

We add 7.5x to both sides of equality:

We subtract 72 from both sides of equality:

We divide between 3 on both sides of equality

ANswer:
Distributive property
Add similar terms
Equality property of the sum
Equality subtraction property
Equality property of the division