Решите уравнения.
1. -6х-х^2=9
2. 2+x^2=11x
3. -9-4x^+12x=0
4. 4+9x^2=0
5. 10x+25x^2=-1
6. x^2+2,3x=0
7. -15=-3x^2
8. -x^2=2+2x
9. 4+3x^2=-7x
10. 14-x-3x^2=0
11. x^2+25=10x
12. -8+18x-5x^2