Example

Solving x+13x27x+10=6x54x2\frac{x+13}{x^2-7x+10} = \frac{6}{x-5} - \frac{4}{x-2}

Solve the rational equation x+13x27x+10=6x54x2\frac{x+13}{x^2-7x+10} = \frac{6}{x-5} - \frac{4}{x-2} by applying the five-step strategy for equations with rational expressions.

Step 1 — Identify restricted values. Factor the quadratic denominator: x27x+10=(x5)(x2)x^2 - 7x + 10 = (x-5)(x-2). Setting each factor equal to zero gives x=5x = 5 and x=2x = 2. Record xeq5x eq 5 and xeq2x eq 2.

Step 2 — Find the LCD. The factored denominators are (x5)(x2)(x-5)(x-2), (x5)(x-5), and (x2)(x-2). The LCD is (x5)(x2)(x-5)(x-2).

Step 3 — Clear the fractions. Multiply every term on both sides by the LCD (x5)(x2)(x-5)(x-2) and cancel matching denominator factors:

(x5)(x2)x+13(x5)(x2)=(x5)(x2)6x5(x5)(x2)4x2(x-5)(x-2) \cdot \frac{x+13}{(x-5)(x-2)} = (x-5)(x-2) \cdot \frac{6}{x-5} - (x-5)(x-2) \cdot \frac{4}{x-2}

Simplify each term to obtain a fraction-free equation:

x+13=6(x2)4(x5)x+13 = 6(x-2) - 4(x-5)

Step 4 — Solve the resulting equation. Distribute on the right: x+13=6x124x+20x+13 = 6x - 12 - 4x + 20. Combine like terms: x+13=2x+8x+13 = 2x + 8. Subtract xx from both sides: 13=x+813 = x + 8. Subtract 88 from both sides: x=5x = 5.

Step 5 — Check. The algebraic solution x=5x = 5 matches one of the restricted values recorded in Step 1, which would make the denominators (x5)(x-5) and (x27x+10)(x^2-7x+10) equal to zero. Therefore, x=5x = 5 is an extraneous solution and must be discarded.

Because the only candidate solution is extraneous, the original equation has no solution.

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Updated 2026-04-30

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