1x+4−1x−7=1130;x≠−4,7\frac{1}{x+4} - \frac{1}{x-7} = \frac{11}{30} ; \quad x \neq -4, 7 Find the value of ' xx '.

Answer: x=1x = 1 or x=2x = 2

Step-by-step solution

Step 1: Combine the fractions on the left-hand side

To solve the equation, we take the common denominator (x+4)(x−7)(x + 4)(x - 7) for the terms on the left-hand side. Subtracting the numerators gives (x−7)−(x+4)(x - 7) - (x + 4).

Step 2: Simplify the numerator and expand the denominator

Simplifying the numerator gives x−7−x−4=−11x - 7 - x - 4 = -11. Expanding the denominator gives (x+4)(x−7)=x2−7x+4x−28=x2−3x−28(x + 4)(x - 7) = x^2 - 7x + 4x - 28 = x^2 - 3x - 28.

Step 3: Cross-multiply and reduce to standard quadratic form

Dividing both sides by 1111 simplifies the equation to −1x2−3x−28=130\frac{-1}{x^2 - 3x - 28} = \frac{1}{30}. Cross-multiplying gives x2−3x−28=−30x^2 - 3x - 28 = -30, which rearranges to x2−3x+2=0x^2 - 3x + 2 = 0.

Step 4: Factor the quadratic equation

We factor the quadratic polynomial by splitting the middle term −3x-3x into −1x-1x and −2x-2x, since (−1)×(−2)=2(-1) \times (-2) = 2. This factors into (x−1)(x−2)=0(x - 1)(x - 2) = 0.

Step 5: Solve for x

Setting each factor to zero gives x=1x = 1 or x=2x = 2. Both values satisfy the original condition x≠−4,7x \neq -4, 7.

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