1. **Stating the problem:** We are given a pattern of equations: $$1 + 4 = 5$$ $$2 + 5 = 12$$ $$3 + 6 = 21$$ $$8 + 11 = ?$$ We need to find the value of the last equation based on the pattern. 2. **Observing the pattern:** The sums on the right side are not simple additions. Let's analyze the first three equations: - For $1 + 4 = 5$, note that $1 \times 4 + 1 = 4 + 1 = 5$ - For $2 + 5 = 12$, note that $2 \times 5 + 2 = 10 + 2 = 12$ - For $3 + 6 = 21$, note that $3 \times 6 + 3 = 18 + 3 = 21$ 3. **Formula used:** The pattern follows: $$a + b = a \times b + a$$ 4. **Applying the formula to the last equation:** $$8 + 11 = 8 \times 11 + 8 = 88 + 8 = 96$$ 5. **Final answer:** $$8 + 11 = 96$$