1. **State the problems:** We need to solve each arithmetic expression involving multiplication and division of integers. 2. **Recall rules:** - Multiplying two numbers with the same sign gives a positive result. - Multiplying two numbers with different signs gives a negative result. - Dividing two numbers with the same sign gives a positive result. - Dividing two numbers with different signs gives a negative result. 3. **Solve each expression:** - $2 \times -4 = -8$ - $-12 \div -3 = 4$ - $-42 \div 6 = -7$ - $-6 \times 8 = -48$ - $50 \div -5 = -10$ - $-3 \times -3 = 9$ - $-90 \div 9 = -10$ - $-10 \times -9 = 90$ - $42 \div -6 = -7$ - $-10 \times 9 = -90$ 4. **Find the difference between $-2 \times -4$ and $-7 \times -8$:** - Calculate $-2 \times -4 = 8$ - Calculate $-7 \times -8 = 56$ - Difference $= 8 - 56 = -48$ **Final answers:** - $2 \times -4 = -8$ - $-12 \div -3 = 4$ - $-42 \div 6 = -7$ - $-6 \times 8 = -48$ - $50 \div -5 = -10$ - $-3 \times -3 = 9$ - $-90 \div 9 = -10$ - $-10 \times -9 = 90$ - $42 \div -6 = -7$ - $-10 \times 9 = -90$ - Difference between $-2 \times -4$ and $-7 \times -8$ is $-48$