Find the nonpermissable replacement for x in this expression x^2/-4x-8

The correct answer for the exercise shown above is: x=-2

 The explanation is shown below:

 1. You have the following expresssion given in the problem above:

 x²/-4x-8

 2. By definition, the nonpermissible replacement for x in this expression, is the value of x that makes the denominator equal to zero.

 3. Keeping this on mind, you have:

 -4x-8=0
 -4x=8
 x=8/-4
 x=-2

  x²/-4x-8= (-2)²/(-4)(-2)-8= 4/8-8= 4/0

 Therefore, as you can see, the answer is x=-2.