Question

For what value of x is the rational expression below undefined? x-4 / 4+x a. 0 b. -4 c. -1 d. 4

Answer 1

b)

Explanation:

`(x-4)/(4+x)\ and\ 4+x\\eq 0\ (we\ can't\ divide\ by\ 0)`

`4+x\\eq 0\\x\\eq -4`

Answer 2

The answer is option b. -4

Explanation:

Given:
`(x-4)/(4+x)`

the rational expression will be undefined at the zeros of the denominator

To find the zeros of the denominator

the denominator = 0

∴ 4 + x = 0

∴ x = -4

So, the rational expression will be undefined at x = -4

The answer is option b. -4