1. The problem is to find the solution for variables $a$ and $b$ given an equation or system involving them. 2. Since the problem statement is vague, let's assume a simple linear system: $a + b = 0$. 3. The formula used is the system of linear equations and the rules of algebra to isolate variables. 4. From $a + b = 0$, we can isolate $a$ as $a = -b$. 5. This means $a$ and $b$ are opposites; if $b$ is known, $a$ is its negative. 6. Without additional information, the solution is expressed as $a = -b$. 7. This is the general solution for the given relation between $a$ and $b$.