Which of the following is a simplified, equivalent form of the rational expression 6(x2−4x)+3(2x−8)2(x2−2x)+(−2x−8)

?(1 point)
Responses

3
3

6x2−18x−242x2−6x−8
Start Fraction 6 x squared minus 18 x minus 24 over 2 x squared minus 6 x minus 8 End Fraction

1
1

3x2+15x−12x2−3x−4

1 answer

To simplify the given rational expression \( \frac{6(x^2 - 4x) + 3(2x - 8)}{2(x^2 - 2x) + (-2x - 8)} \), we will first simplify the numerator and the denominator separately.

Step 1: Simplify the numerator

  1. Expand \( 6(x^2 - 4x) \): \[ 6x^2 - 24x \]

  2. Simplify \( 3(2x - 8) \): \[ 6x - 24 \]

  3. Combine the results for the numerator: \[ 6x^2 - 24x + 6x - 24 = 6x^2 - 18x - 24 \]

Step 2: Simplify the denominator

  1. Expand \( 2(x^2 - 2x) \): \[ 2x^2 - 4x \]

  2. Combine it with \( -2x - 8 \): \[ 2x^2 - 4x - 2x - 8 = 2x^2 - 6x - 8 \]

Step 3: Combine the simplified results

Now we have the rational expression as: \[ \frac{6x^2 - 18x - 24}{2x^2 - 6x - 8} \]

Step 4: Factor both parts if possible

  • For the numerator \( 6x^2 - 18x - 24 \): \[ = 6(x^2 - 3x - 4) = 6(x - 4)(x + 1) \quad \text{(factoring the quadratic)} \]

  • For the denominator \( 2x^2 - 6x - 8 \): \[ = 2(x^2 - 3x - 4) = 2(x - 4)(x + 1) \quad \text{(factoring the quadratic)} \]

Step 5: Simplify the overall expression

Now, the rational expression becomes: \[ \frac{6(x - 4)(x + 1)}{2(x - 4)(x + 1)} \]

Since \( (x - 4)(x + 1) \) cancels out: \[ = \frac{6}{2} = 3 \]

Thus, the simplified equivalent form is: \[ 3 \]

Therefore, the correct response is 3.