1. The problem is to show the work for solving an algebraic or mathematical expression or equation. 2. Since no specific problem was given, I will demonstrate solving a simple linear equation: $2x + 3 = 7$. 3. The formula or rule used here is to isolate the variable $x$ by performing inverse operations. 4. First, subtract 3 from both sides: $$2x + 3 - 3 = 7 - 3$$ which simplifies to $$2x = 4$$ 5. Next, divide both sides by 2 to solve for $x$: $$\frac{\cancel{2}x}{\cancel{2}} = \frac{4}{2}$$ which simplifies to $$x = 2$$ 6. Therefore, the solution to the equation $2x + 3 = 7$ is $x = 2$. 7. This process shows how to isolate the variable step-by-step using inverse operations and simplification.