Question

Which of the following values of x makes the rational expression below undefined?

Problem : 16-x/7+x
A. 7
B. -7
C. 16
D. -16

Answer 1

B. -7
When the denominator equals zero, that makes it undefined

Answer 2

Answer: The correct option is (B) -7.

Step-by-step explanation: We are given to select the correct values of x that make the following rational expression undefined :

`E=(16-x)/(7+x)~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~(i)`

We know that

a rational expression is undefined at the points where the denominator becomes zero.

Therefore, the expression (i) will become undefined when

`7+x=0\\\\\Rightarrow x=-7.`

Thus, the required value of x where the given expression is undefined is -7.

Option (B) is CORRECT.