Mathematics for IGCSE & O level - Equations (Section 4 - No. 16)
What is the first step when changing the subject of a formula?
Rearrange the terms.
Isolate the unknown.
Simplify and collect terms.
Use inverse operations to get the unknown on its own.
Paliwanag
The first step is usually to simplify and collect terms, if necessary, before isolating the subject.