6. √21 − 4 = −х 7. √54 − 3 = −х 8. √30 − = −х 9. √56 + = −х 10. √28 + 3 = −х 11. √36 + 5...

Question

6. √21 − 4 = −х
7. √54 − 3 = −х
8. √30 − = −х
9. √56 + = −х
10. √28 + 3 = −х
11. √36 + 5 = −х
12. √14 − 5 = х
13. √28 − 3 = х
14. √2 − = х
15. √12 + = х
16. √48 + 2 = х
17. √21 + 4 = х
18. √−8 + 6 = х
19. √18 + 7 = х
20. √−8 + 9 = х
21. √−35 + 12 = х
22. √−56 + 15 = х
23. √2 + 3 = х
24. √15 − 2 = х
25. √2 + 3 = −х
26. √6 + 5 = х

Answer 1

6.21-4х=х^2
x^2+4x-21=0
D=16+84=100>0
x1=(-4-10)/2=-14/2=-7
x2=(-4+10)/2=6/2=3
7.54-3x=x^2
x^2+3x-54=0
D=9+216=225>0
x1=(-3-15)/2=-18/2=-9
x2=(-3+15)/2=12/2=6
8.30-x=x^2
x^2+x-30=0
D=1+120=121>0
x1=(-1-11)/2=-12/2=-6
x2=(-1+11)/2=10/2=5
9.56+x=x^2
x^2-x-56=0
D=1+224=225>0
x1=(1-15)/2=-14/2=-7
x2=(1+15)/2=16/2=8