P=S1 + S2 +S3 for S2

To isolate the variable S2 in the equation P = S1 + S2 + S3, we can follow these steps:

1. Start with the original equation: P = S1 + S2 + S3.
2. Subtract S1 from both sides of the equation: P - S1 = S2 + S3.
3. Simplify the right side of the equation: P - S1 = S3 + S2.
4. Rearrange the equation to isolate S2: P - S1 - S3 = S2.

Therefore, the equation to solve for S2 is S2 = P - S1 - S3.