1. **State the problem:** Solve the equation $7x + 12 = (x + 3)(x + 4)$ and understand how the factors 3 and 4 appear.
2. **Expand the right side:** Use the distributive property (FOIL) to expand $(x + 3)(x + 4)$:
$$ (x + 3)(x + 4) = x \cdot x + x \cdot 4 + 3 \cdot x + 3 \cdot 4 = x^2 + 4x + 3x + 12 = x^2 + 7x + 12 $$
3. **Rewrite the equation:** Now the equation is
$$ 7x + 12 = x^2 + 7x + 12 $$
4. **Bring all terms to one side:** Subtract $7x + 12$ from both sides:
$$ 7x + 12 - 7x - 12 = x^2 + 7x + 12 - 7x - 12 $$
$$ 0 = x^2 $$
5. **Simplify:** This simplifies to
$$ x^2 = 0 $$
6. **Solve for $x$:** Taking the square root of both sides,
$$ x = 0 $$
7. **Explanation of factors 3 and 4:** The numbers 3 and 4 come from the original factorization of the quadratic expression on the right side. The expression $x^2 + 7x + 12$ factors into $(x + 3)(x + 4)$ because 3 and 4 are two numbers that multiply to 12 (the constant term) and add to 7 (the coefficient of $x$).
**Final answer:**
$$ x = 0 $$
Factorization Explanation Cb1Ddd
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