From

A. X could be +3 or -3. Not sufficient

B. Again not sufficient

Combining the options won't be of any benefit.. so E

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Target question: Is x ≥ 3 ?

Statement 1: x² - 9 = 0
Add 9 to both sides of the equation to get: x² = 9
When we solve this we see that EITHER x = 3 OR x = -3
Let's examine both possible cases:
Case a: If x = 3, then the answer to the target question is YES, it is the case that x ≥ 3
Case b: If x = -3, then the answer to the target question is NO, it is not the case that x ≥ 3
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: x < 10
There are several values of x that satisfy statement 2. Here are two:
Case a: If x = 9, then the answer to the target question is YES, it is the case that x ≥ 3
Case b: If x = 0, then the answer to the target question is NO, it is not the case that x ≥ 3
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
Statement 1 tells us that EITHER x = 3 OR x = -3
Notice that both of these possible x-values are less than 10.
If x = 3, then the answer to the target question is YES, it is the case that x ≥ 3
If x = -3, then the answer to the target question is NO, it is not the case that x ≥ 3
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT

Answer: E

Cheers,
Brent
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