1. The answer is: Let B (-6,0) and C (6 6,0) intersect (0,4.5) to make a straight line parallel to the X axis, then A should be located on this straight line, defined by the first ellipse (or as the symmetrical point D of C about this straight line, AC=AD is better explained), and know that A is in (.

2. The answer is: 1

3. The answer is: a>0

4. The answer is:-1< a <; 0 or a> 1

5. The answer is: x=-2.8 or -3.2.

6. The answer is:

7. The answer is: 256

Sorry, the following steps are too difficult to write. You can find a way by testing the answers.