Question

For which rational expression is 8 an excluded value ? check all that apply

Answer 1

C. x^2+5/x-8

D. x^2-x-56/x^2-64

Explanation:

just did the assignment and can confirm the answer above me is correct

Answer 2

The correct answer options are C.
`(x^2+5)/(x-8)` and D.
`(x^2-x-56)/(x^2-64)`.

Explanation:

The values which make the denominator equal to zero are called the excluded values.

Here, we can substitute 8 for x and check if it makes the denominator 0.

`(x-8)/(x+8) = (8-8)/(8+8) =(0)/(16) =0`

`(x-2)/(x^2-4) = (8-2)/(8^2-4) =(6)/(60) =(1)/(10)`

`(x^2+5)/(x-8) = (8^2+5)/(8-8) =(69)/(0)`

`(x^2-x-56)/(x^2-64) = (8^2-8-56)/(8^2-64) = (0)/(0) =0`

`(8x^2-2)/(x^2-16) = (8(8)^2-2)/(8^2-16) =(510)/(48)`