1. The expression given is $3x + 6y$. 2. This is a linear algebraic expression involving two variables $x$ and $y$. 3. We can factor out the common factor of 3 from both terms to simplify the expression. 4. Factoring out 3, we get $$3x + 6y = 3(x + 2y)$$. 5. So, the simplified form of the expression is $$3(x + 2y)$$. 6. This shows the expression as a product of 3 and the sum $(x + 2y)$, which can be useful for solving equations or further manipulation.