\( \left. \begin{array} { l } { a ( b + c ) = } \\ { x ( y - z ) = } \\ { x ( 2 y + 3 ) = } \\ { 2 a ( 3 b - c ) = } \\ { 3 x ( 2 - 3 y ) = } \end{array} \right. \)

If you're looking at an expression involving products and sums, you can often use the distributive property to simplify things. For example, in the first expression, \( a(b + c) \) can be expanded to \( ab + ac \). Simplifying in this way can help you see the relationships between different variables more clearly. When working with equations like these, it’s crucial to remember to keep track of your variables and the operations performed on them. A common mistake is to drop a sign or misplace a coefficient. Always double-check your work, especially when multi-step operations (like solving for a variable) are involved, to ensure you’re not mixing up terms!