How do you know when to use the subtraction property of equality as a reason as opposed to subtraction of real numbers?

Subtraction property of equality is used when u have 2 sides with an equal sign in the middle and u want to subtract from both sides.

Example:

2x + 3 = 7 ... subtract 3 from both sides

2x + 3 - 3 = 7 - 3

2x = 4

x = 4/2

x = 2

When subtracting real numbers ... if the numbers are on the same side of the equal sign ... u can just subtract on that one side

Example:

2x = 7 - 3

2x = 4

x = 4/2

x = 2