1. **State the problem:** Solve the equation $9x - 12x + 4 = 0$ for $x$. 2. **Combine like terms:** The terms $9x$ and $-12x$ are like terms and can be combined. $$9x - 12x = (9 - 12)x = -3x$$ So the equation becomes: $$-3x + 4 = 0$$ 3. **Isolate the variable term:** Subtract 4 from both sides to isolate the term with $x$. $$-3x + 4 - 4 = 0 - 4$$ $$-3x = -4$$ 4. **Solve for $x$:** Divide both sides by $-3$ to solve for $x$. $$x = \frac{-4}{-3}$$ Show cancellation of negatives: $$x = \frac{\cancel{-4}}{\cancel{-3}} = \frac{4}{3}$$ 5. **Final answer:** $$x = \frac{4}{3}$$