metallicafan wrote:If 9 - x2 ≥ 0 , which of the following describes all possible values of x ?

A. 3 ≥ x ≥ -3

B. x ≥ 3 or x ≤ -3

C. 3 ≥ x ≥ 0

D. -3 ≥ x

E. 3 ≤ x

NOTE: I'm assuming that you meant to write 9 - x^2 > 0

Given: 9 - x^2 > 0
Add x^2 to both sides: 9 > x^2
At this point we may see that it must be true that -3 < x < 3
Answer = A

Alternatively, once we know that 9 > x^2 we can find some values for x that satisfy this inequality.
For example, if 9 > x^2, then x = -2 is one possible value for x.
Now check the answer choices to see which one(s) allows for x to equal -2

Only answer choice A allows for the possibility that x = -2

So, the correct answer must be A

Cheers,
Brent