1. **State the problem:** Add the rational expressions $$\frac{5}{x-7} + \frac{x-3}{x-4}$$ and simplify the result as much as possible.
2. **Formula and rules:** To add rational expressions, find a common denominator, which is usually the least common denominator (LCD) of the denominators.
3. **Find the LCD:** The denominators are $x-7$ and $x-4$. The LCD is $(x-7)(x-4)$.
4. **Rewrite each fraction with the LCD:**
$$\frac{5}{x-7} = \frac{5(x-4)}{(x-7)(x-4)}$$
$$\frac{x-3}{x-4} = \frac{(x-3)(x-7)}{(x-4)(x-7)}$$
5. **Add the numerators over the common denominator:**
$$\frac{5(x-4) + (x-3)(x-7)}{(x-7)(x-4)}$$
6. **Expand the numerators:**
$$5(x-4) = 5x - 20$$
$$(x-3)(x-7) = x^2 - 7x - 3x + 21 = x^2 - 10x + 21$$
7. **Combine the expanded numerators:**
$$5x - 20 + x^2 - 10x + 21 = x^2 - 5x + 1$$
8. **Write the final expression:**
$$\frac{x^2 - 5x + 1}{(x-7)(x-4)}$$
9. **Check for further simplification:** The numerator $x^2 - 5x + 1$ does not factor nicely, so this is the simplified form.
**Final answer:**
$$\frac{x^2 - 5x + 1}{(x-7)(x-4)}$$
Add Rational Expressions
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