1. **Problem 45: Solve the equation** $\frac{x}{9} = 4$. 2. The formula used here is to isolate $x$ by multiplying both sides of the equation by 9: $$x = 4 \times 9$$ 3. Multiply to find $x$: $$x = 36$$ 4. So, the solution to the equation is $x = 36$. --- 5. **Problem 46: Use long division to find** $43210 \div 5$. 6. Long division steps: - Divide 43 by 5, which goes 8 times (since $5 \times 8 = 40$), remainder 3. - Bring down the next digit 2, making 32. - Divide 32 by 5, which goes 6 times ($5 \times 6 = 30$), remainder 2. - Bring down the next digit 1, making 21. - Divide 21 by 5, which goes 4 times ($5 \times 4 = 20$), remainder 1. - Bring down the last digit 0, making 10. - Divide 10 by 5, which goes 2 times ($5 \times 2 = 10$), remainder 0. 7. Putting it all together, the quotient is 8642. **Final answers:** - For question 45: $x = 36$ - For question 46: $43210 \div 5 = 8642$