Bx=y+z
Change the subject of it which is x

Dear Student.

To make 'y' the subject of the formula, subtract z from both sides.
We get: Bx - z = y + z - z
y = Bx - z
To make 'z' the subject of the formula, subtract y from both sides.
Bx - y = y + z - y
z = Bx - y

We hope that this answer solves your query.
Regards.