1. **State the problem:** Simplify the expression $2y + 9y(5x + 6b)3x + 7b$. 2. **Apply the distributive property:** First, multiply $9y$ by the expression $(5x + 6b)$ and then multiply the result by $3x$. 3. **Calculate inside the parentheses:** $$9y(5x + 6b)3x = 9y \times (5x + 6b) \times 3x$$ 4. **Distribute $9y$ over $(5x + 6b)$:** $$9y \times 5x = 45xy$$ $$9y \times 6b = 54yb$$ 5. **Multiply each term by $3x$:** $$45xy \times 3x = 135x^2y$$ $$54yb \times 3x = 162xyb$$ 6. **Rewrite the expression:** $$2y + 135x^2y + 162xyb + 7b$$ 7. **Combine like terms if any:** There are no like terms to combine. **Final simplified expression:** $$2y + 135x^2y + 162xyb + 7b$$