Question: Add. $-1 + (-3) = \square$ $5 + (-2) = \square$

1. **State the problem:** We need to find the sums of $-1 + (-3)$ and $5 + (-2)$. 2. **Recall the rule for adding integers:** When adding two negative numbers, add their absolute values and keep the negative sign. When adding a positive and a negative number, subtract the smaller absolute value from the larger and keep the sign of the number with the larger absolute value. 3. **Calculate $-1 + (-3)$:** $$-1 + (-3) = -(1 + 3) = -4$$ Explanation: Both numbers are negative, so add their absolute values $1 + 3 = 4$ and keep the negative sign. 4. **Calculate $5 + (-2)$:** $$5 + (-2) = 5 - 2 = 3$$ Explanation: One positive and one negative number, subtract $2$ from $5$ and keep the positive sign because $5$ is larger. **Final answers:** $-1 + (-3) = -4$ $5 + (-2) = 3$