1. **State the problems:** Solve the linear equations from question 9 to 13. 2. **General formula and rules:** For linear equations of the form $ax + b = c$, isolate $x$ by subtracting or adding terms and then dividing by the coefficient $a$. --- **Question 9: Solve $8 - 3x = -4$** 3. Subtract 8 from both sides: $$8 - 3x - 8 = -4 - 8$$ $$-3x = -12$$ 4. Divide both sides by $-3$: $$x = \frac{-12}{-3}$$ $$x = 4$$ --- **Question 10: Solve $-13 + 4x = 7$** 5. Add 13 to both sides: $$-13 + 4x + 13 = 7 + 13$$ $$4x = 20$$ 6. Divide both sides by 4: $$x = \frac{20}{4}$$ $$x = 5$$ --- **Question 11: Solve $8 - 5x = 17$** 7. Subtract 8 from both sides: $$8 - 5x - 8 = 17 - 8$$ $$-5x = 9$$ 8. Divide both sides by $-5$: $$x = \frac{9}{\cancel{-5}} \times \frac{\cancel{-1}}{1} = -\frac{9}{5}$$ --- **Question 12: Solve $-9 + 2x = 13$** 9. Add 9 to both sides: $$-9 + 2x + 9 = 13 + 9$$ $$2x = 22$$ 10. Divide both sides by 2: $$x = \frac{22}{2}$$ $$x = 11$$ --- **Question 13: Solve $5x - 4 = -3$** 11. Add 4 to both sides: $$5x - 4 + 4 = -3 + 4$$ $$5x = 1$$ 12. Divide both sides by 5: $$x = \frac{1}{5}$$ --- **Final answers:** - Question 9: $x = 4$ - Question 10: $x = 5$ - Question 11: $x = -\frac{9}{5}$ - Question 12: $x = 11$ - Question 13: $x = \frac{1}{5}$