3.) \( 7 y=\frac{(x+4)}{2} \).

Let’s dive into the historical context of equations like this one! The use of algebraic equations can be traced back to ancient civilizations, with notable contributions from Indian mathematician Brahmagupta in the 7th century, who developed systematic methods for solving linear equations. It wasn’t until the 16th and 17th centuries in Europe that algebra began to take on the symbolic form we recognize today, paving the way for modern mathematics. Now, let's bring some real-world application into the mix! Equations like this one are essential in fields such as physics, engineering, and economics. For instance, you might use a linear equation to model the relationship between the distance traveled by a vehicle and time, helping to predict when it will arrive at its destination. These practical applications show just how vital algebra is in our daily lives!