anonymous one year ago Write the equation of an ellipse with vertices (0, 5) and (0, -5) and co-vertices (2, 0) and (-2, 0).

1. anonymous

|dw:1439646942183:dw|

2. anonymous

a=5 b=2

3. anonymous

5^2=25 2^2=4

4. anonymous

y2/25 + x2/4 = 1? the horizontal get me mixed up sometimes but i feel thats right

5. Loser66

How to say!!! You are an EXPERT now. hehehe

6. anonymous

only bc u took the time to teach my slow mind lol thank you, now..can u teach me hyperbola? those confuess me more then anything @Loser66

7. Loser66

Let's look at it first. I am not sure whether I can or not. One more thing, you have only 15 more minutes. I have to go after then.

8. anonymous

one more thing! Ellipses have symmetry through only their major axis? true or false? lol

9. anonymous

i think its false?

10. Loser66

through both axis

11. anonymous

so its false

12. Loser66

yup

13. Loser66

To hyperbola, everything is the same with ellipse but the - sign

14. anonymous

okay. ill start a new post.

15. Loser66

a goes with main axis b goes with co-axis. and c^2 = a^2 + b^2 (opposite with ellipse, which is c^2 =a^2 -b^2\)

16. Loser66

why a new post. It is good here

17. anonymous

okay- What are the asymptotes of the following graph?

18. Loser66

|dw:1439647512939:dw|

19. anonymous

|dw:1439647585256:dw|

20. Loser66

ok, |dw:1439647624382:dw|

21. Loser66

Do you know how to find the slope of this line?

22. anonymous

one sec.

23. anonymous

m=y1-y2/x1-x2

24. Loser66

yes, =?

25. anonymous

m=-3-3/-1-1

26. Loser66

nope

27. Loser66

You plug in x1-x2 on top. it is not right,

28. anonymous

y=-1-1/-3-3

29. Loser66

yup, =?

30. anonymous

m=-2/-6 m=2/6 m=1/3

31. Loser66

Bingo

32. Loser66

Hence the asymptote of the hyperbola is just $$y =\pm\dfrac{1}{3}x$$

33. anonymous

okay i get it. can we get 1 more in really quickly?

34. Loser66

3 minutes for that.

35. anonymous

What is the center of the following graph?

36. Loser66

|dw:1439648000091:dw|

37. anonymous

(1,2)

38. Loser66

yup

39. anonymous

u think we can solve for a foci or not enough time?

40. Loser66

not enough

41. Loser66

but I can give you a guidance: find asymptote, it is the form of a/b, take that a, b to solve for c which is foci.