1. **State the problem:** Add the two expressions $2x - 7y + 8z$ and $3x + 2y$. 2. **Write the expressions:** $$2x - 7y + 8z$$ $$3x + 2y$$ 3. **Add like terms:** - Combine $x$ terms: $2x + 3x = 5x$ - Combine $y$ terms: $-7y + 2y = -5y$ - The $z$ term has no like term, so it remains $8z$ 4. **Write the final expression:** $$5x - 5y + 8z$$ This is the sum of the two expressions.