For what value of x is the rational expression below undefined? check all that apply  x+8/x^2-2x-24a.4b.-4c.-6d.-8e.8f.6

I can only guess that by x^2-2x-24 you mean the entire denominator.  In cases like this is is important to use parentheses to remove any doubts.  For example:

(x+8) / (x^2-2x-24).

This rational expression is undefined at any x for which the denominator, x^2-2x-24, is zero.  

x^2-2x-24 factors into (x+4)(x-6).  The roots are -4 and +6.  

Thus, the given expression is undefined at {-4,6} (set notation).

the correct answer is

c. 4

step-by-step explanation:

the given polynomial is

the degree of the polynomial is the highest exponent which is 4.

the -4 is called the leading coefficient.

this polynomial has only one term so it is a monomial.

the correct answer is option c.