Question: 5. Solve the equation $$(x - 10)(x + 20) = 0$$.
Solve the equation $$(3x + 4)(x - 4) = 0$$.
1. **State the problem:**
We need to solve the equation $$(x - 10)(x + 20) = 0$$.
2. **Recall the zero product property:**
If the product of two factors is zero, then at least one of the factors must be zero. That is,
$$ (x - 10)(x + 20) = 0 \implies x - 10 = 0 \text{ or } x + 20 = 0 $$
3. **Solve each equation separately:**
- For $$x - 10 = 0$$, add 10 to both sides:
$$ x = 10 $$
- For $$x + 20 = 0$$, subtract 20 from both sides:
$$ x = -20 $$
4. **Final solution:**
The solutions to the equation are $$x = 10$$ and $$x = -20$$.
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Now, solve the equation $$(3x + 4)(x - 4) = 0$$.
5. **Apply zero product property:**
$$ (3x + 4)(x - 4) = 0 \implies 3x + 4 = 0 \text{ or } x - 4 = 0 $$
6. **Solve each equation:**
- For $$3x + 4 = 0$$, subtract 4 from both sides:
$$ 3x = -4 $$
Then divide both sides by 3:
$$ x = \frac{\cancel{3}x}{\cancel{3}} = \frac{-4}{3} $$
- For $$x - 4 = 0$$, add 4 to both sides:
$$ x = 4 $$
7. **Final solution:**
The solutions to the equation are $$x = -\frac{4}{3}$$ and $$x = 4$$.