## lsugano 3 years ago i want to find the area of a triangle with the given angles A=32˚ C= 77˚ a=71cm. I got the answer about 48.5sqcm but the answer says 170sqcm..How is this possible? click attached. http://bamboodock.wacom.com/doodler/0cb3063d-8c0b-4902-82c1-055993bc5aba

1. godorovg

you on?

2. lsugano

yes i am! my computer froze

3. godorovg

okay no biggie

4. godorovg

let me ask some questions here. First when you did the work did you check the signs like + - because the could cause a problem also in the first part explain this a little I am just trying to understand

5. lsugano

um i think i am doing it right.

6. godorovg

okay than where did 180 come from?

7. godorovg

I did to know the whole problem not just answers

8. lsugano

180 is the total of the 3 angles of the traignle

9. lsugano

since i know A=32 and C=77 B= 71 from 180-32-77

10. godorovg

did you plug for for these?

11. godorovg

did you a and put in it for a

12. lsugano

the formula to find an area of a triangle with 2 angles and one side given is area= a^2sinBsinC / 2sinA

13. lsugano

so i did like this

14. lsugano

am i wrong or is this book stupid...? lol

15. alexwee123

im just curious is this geometry or trig? o.0

16. lsugano

its in trig.

17. alexwee123

oh ok then maybe you can check this site out http://www.regentsprep.org/Regents/math/algtrig/ATT13/areatriglesson.htm it gives a better formula and solution :D

18. cfraser007

ok ok...i think u should try to change your calculator settings to degrees and not radians!

19. lsugano

its in degrees...i already tried doing that...

20. godorovg

21. cfraser007

wait a seocnd...i'll put my numbers up...i got approximately 170.3...check for yourself...

22. godorovg

same here..

23. lsugano

i got 61.63 but the book says 170...

24. godorovg

I think the second part is wrong somehow

25. cfraser007

|dw:1344138495546:dw|

26. godorovg

yep that is what is wrong forgot to put the a b c in the problem

27. godorovg

in other words sub in

28. lsugano

wait how did you get 180.57.?? i cant got 188.36

29. cfraser007

ok...lets take even more baby steps! what did u get for sin71 x sin77?

30. godorovg

cfraser should I go and let you help or stay??

31. cfraser007

i can help...i guess...!

32. lsugano

sin77= 0.9744 sin71= 0.9455

33. lsugano

im so sorry ><

34. cfraser007

y?

35. lsugano

for making you guys have a hard time....

36. godorovg

37. lsugano

thank you! so does this look okay so far?

38. cfraser007

haha! no problem...most of us are here to help and make ourselves feel better anyways! lol...and actually 186 is right! (i mistyped!)

39. cfraser007

what did u get for 2sin32?

40. godorovg

ha ha typo wow get love trig on a computer ha ha

41. lsugano

2sin32 = 1.0598

42. cfraser007

okay...so, divide those two numbers!

43. cfraser007

dont round them up like me! the more digits...the better!!

44. lsugano

i got 177.39

45. godorovg

yes

46. cfraser007

hmm...so...thats much closer to 170! lol

47. lsugano

isnt it lose to 180....?lol

48. godorovg

yeah, but who is keeping track lol

49. cfraser007

better than 48.5! :)

50. godorovg

lol

51. lsugano

HEY i got it

52. cfraser007

sweet! great!!

53. godorovg

GREAT JOB!!

54. lsugano

thanks a lottttt!!!!

55. godorovg

56. cfraser007

same feeling here!

57. godorovg

cfraser007 nice job!!

58. cfraser007

thanks :D!