What's the standard equation of the circle with the general equation x2 + y2 + 4x – 2y – 20 = 0? answers: 1) (x + 2)2 + (y – 1)2 = 5 2) (x – 2)2 + (y + 1)2 = 25 3) (x + 1)2 + (y – 2)2 = 5 4) (x + 2)2 + (y – 1)2 = 25

4).  (x + 2)^2 + (y - 1)^2 = 25.

Step-by-step explanation:

x^2 + y^2 + 4x - 2y - 20 = 0

x^2 + 4x + y^2 - 2y = 20

Completing the square on the x and y terms:

(x + 2)^2  - 4 + (y - 1)^2 - 1 = 20

(x + 2)^2 + (y - 1)^2 = 20 + 4 + 1

(x + 2)^2 + (y - 1)^2 = 25.

if x decreases by 4 then y increases by 10

step-by-step explanation:

1. 3.4/4

2. 0.8/7

3. 0.5 x 3

4. 0.9 x 6

5. 10.8

6. 2.35

7. 0.567

8. 9.35

9. 0.02

10. 0.06

11. 0.16

12. 0.42

13. 0.63

14. 5.6

15. 8.1

16. 9.9

17. 0.28

18. 0.48

19. 0.27

20. 0.49

21. 0.45

22. 0.72

23. 0.9

24. 0.88

25. 0.75

26. 0.16

27. 0.328

28. 0.495

29. 0.72

30. 1.068