What is the least common denominator of the equation 5x+5−1x2+2x−15=4x2+2x−15 ?(1 point)%0D%0AResponses%0D%0A%0D%0A(x+5)(x−3)%0D%0Aleft parenthesis x plus 5 right parenthesis left parenthesis x minus 3 right parenthesis%0D%0A%0D%0A(x+5)%0D%0Aleft parenthesis x plus 5 right parenthesis%0D%0A%0D%0A(x+5)(x2+2x−15)%0D%0Aleft parenthesis x plus 5 right parenthesis left parenthesis x squared plus 2 x minus 15 right parenthesis%0D%0A%0D%0A(x+5)(x2+2x−15)(x2+2x−15)

1 answer

To find the least common denominator (LCD) of the equation given, let's start by examining the denominators involved in the equation:

The equation is: \[ \frac{5x + 5}{x^2 + 2x - 15} = \frac{4x^2 + 2x - 15}{1} \]

The only denominator present is \(x^2 + 2x - 15\).

To factor \(x^2 + 2x - 15\):

  1. We need to find two numbers that multiply to \(-15\) (the constant term) and add to \(2\) (the coefficient of \(x\)).
  2. The numbers \(5\) and \(-3\) satisfy these conditions since \(5 \times -3 = -15\) and \(5 + (-3) = 2\).

Thus, we can factor: \[ x^2 + 2x - 15 = (x + 5)(x - 3) \]

So, the least common denominator (LCD) for the equation is: \[ (x + 5)(x - 3) \]

Now, reviewing the response options you provided:

  1. \((x + 5)(x - 3)\)
  2. \((x + 5)\)
  3. \((x + 5)(x^2 + 2x - 15)\)
  4. \((x + 5)(x^2 + 2x - 15)(x^2 + 2x - 15)\)

The correct choice is: \[ \text{(x + 5)(x - 3)} \]