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## anonymous one year ago Can someone please help me solve this!

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1. anonymous

2. Nnesha

$\rm sin \rm \theta = \frac{ opposite }{ hypotenuse }~~~~ \cos \theta = \frac{ adjacent }{ hypotenuse } ~~\tan \theta = \frac{ opposite }{ adjacent }$ that's all you need to find all 6 ratios

3. Nnesha

|dw:1443972456164:dw| tan B = 2/9

4. Nnesha

where you should put 2 and 9 ?

5. Nnesha

remember we are looking at angle B

6. anonymous

|dw:1443972579055:dw|

7. Nnesha

good now apply the Pythagorean theorem to find 3rd side of right triangle

8. anonymous

I got 9^2+2^2=c^2, 81+4=c^2, c^2=85,sqrt(85)=c

9. Nnesha

looks good |dw:1443972735567:dw| now use the definition iposted above to write sin cos and csc

10. anonymous

for cos of B I got 9(sort)/85

11. anonymous

sqrt*

12. Nnesha

looks good and we don't have to rationalize the denominator

13. anonymous

and for cscB i'm not sure what that would be

14. Nnesha

what's the reciprocal of sin ??

15. Nnesha

like cos and sec are reciprocal cos theta = 1/sec theta

16. anonymous

so csc(b)=85/2sqrt(85)?

17. Nnesha

what is sin B = ?

18. anonymous

they are asking for sinA

19. AlexandervonHumboldt2

@sana9 the original definitions were not those which nnesha gives you. please keep in mind that you might have a question like what is sin of 360? you will never find a 360 degrees in a triangle. so the standart school definitions will not work for such question. so keep in mind these universal things: Sinus: sin(a)=(yb)/R Cosine: cos(a)=(xb)/R Tangent: tg(a)=(yb)/(xb) picture : https://upload.wikimedia.org/wikipedia/ru/thumb/8/8f/Trig_functions.gif/250px-Trig_functions.gif sourse wikipedia

20. Nnesha

i know they are asking for sin but what is sin B = ?

21. anonymous

sinb=2sqrt(85)/85

22. Nnesha

look at this definition $\large\rm cos \theta =\frac{ 1 }{ \sec \theta}$$\sin \theta = \frac{ 1 }{ \csc \theta }$$\tan \theta =\frac{ 1 }{ \cot \theta }$ or tan theta = sin/ cos

23. Nnesha

so if you find sin B you can easily find csc B

24. anonymous

for csc(b) I believe it's 85/2sqrt(85)

25. Nnesha

|dw:1443973415613:dw| don't rationalize the denominator

26. Nnesha
27. Nnesha

sin = opposite over hypotenuse so sin B =?

28. anonymous

ok so let me try one more time :)

29. Nnesha

alright take ur time!

30. anonymous

cos(b)=9/sqrt(85)

31. anonymous

csc(b)=sqrt(85)/2

32. Nnesha

|dw:1443973622264:dw| right

33. Nnesha

looks good hm

34. anonymous

sin(a)=9/sqrt(85)

35. Nnesha

right so what's sin B = ???

36. anonymous

sinb=2/sqrt(85)

37. Nnesha

right what about tan a ??

38. anonymous

tan=sin/cos so

39. Nnesha

right

40. Nnesha

so what is the exact value of tan A ?

41. anonymous

1

42. anonymous

so I have another question regarding find sin cos and tan

43. anonymous

this involves side length so I was sure how to work this out!

44. anonymous

wasn't*

45. Nnesha

no it's not 1 remember tan = sin over cos and sin = opposite over hyp cos = adjacent over hyp $\huge\rm tan = \frac{ \frac{ o }{ h } }{ \frac{ a }{ h } }=\frac{o}{h} \times \frac{h}{a}$ multiply top fraction with the reciprocal of the bottom fraction $\huge\rm tan =\frac{o}{\cancel{h}} \times \frac{\cancel{h}}{a}=\frac{o}{a}$ o=opposite a=adjacent so tan = opposite over adjacent

46. anonymous

thank you!

47. Nnesha

np so what is tan A ?? :+)

48. Nnesha

^first question

49. anonymous

2/9?

50. Nnesha

|dw:1443974262921:dw| remember opposite and adjacent sides depends on angle 9 is adjacent side of angle B but 9 is opposite side of angle A adjacent side that touches the angle we are looking at

51. anonymous

9/2!

52. Nnesha

good ! cot =2/9 cot and tan are reciprocal of each other i think u got it just need more practice :=)

53. anonymous

:) thanks so much. I'm sure how to solve angles and length when knowing only 2 side lengths in a right triangle

54. anonymous

not sure*

55. Nnesha

|dw:1443974435122:dw| same question given is b and c

56. Nnesha

good then did you try to find 3rd side ? :=)

57. Nnesha

oh not sure

58. Nnesha

same question like last one one given are the 2 legs of right triangle  then always you can use Pythagorean theorem to find 3rd side

59. anonymous

for a I got that it equal 8

60. anonymous

it's just finding the angles which confuses me :/

61. Nnesha

8 is correct

62. Nnesha

ah i see |dw:1443974659273:dw| just focus one angle A for this question its easy to find angle bec u know all 3 sides you can use any ratio doesn't matter u will get the same answer!

63. Nnesha

|dw:1443974742902:dw|

64. Nnesha

let's pick sin sin A = opposite over adjacent what is opposite and adjacent side of angle A ?

65. anonymous

I thought sin was opposite over hyp

66. Nnesha

right lol sorry mistake thinking about tan

67. anonymous

sin(a) =8/17

68. Nnesha

right $\huge\rm sin A = \frac{ 8 }{ 17}$ when we have to find anlde we use invs sin $\large\rm A = \sin^{-1} \frac{8}{17}$

69. Nnesha

angle **

70. anonymous

so it's 28 degrees

71. Nnesha

let me check :D wait plz

72. anonymous

ok thank you :)

73. Nnesha

right ! good job!

74. anonymous

and to find angle B we would do sin(B)=15/17 which is sin-1(15/17)=61.9 and it's exactly 62?

75. Nnesha

right you can round it if you want or if the direction says so

76. Nnesha

ohh wait directions is NO DECIMAL so round it

77. anonymous

the direction just mentions the exact measure

78. Nnesha

|dw:1443975183145:dw| so no decimal round it

79. anonymous

62 :D

80. Nnesha

good :=)

81. anonymous

i'm having trouble inputting the degrees sign into the answer

82. Nnesha

hmm

83. Nnesha

i guesss you don't have to put degree sign bec it says angle A so definitely the number u will put is an angle hmm i think ....

84. anonymous

it's wanting the degrees symbol :/

85. Nnesha

hmmm does it work $\huge\rm a^o$ i'm not sure how to put on that website

86. Nnesha

is it a practice website or online school documeent ?

87. anonymous

88. anonymous

this is what showed up

89. Nnesha

hmm well i think the answer we got is correct not sure what theyyy want us to do did they gave u the correct ??

90. Nnesha

answer >???*

91. anonymous

no :/

92. anonymous

It makes sense in terms of the math, but when I enter it in the system it's didn't recognize it

93. Nnesha

ye right let me think hmmm

94. Nnesha

how did you put degree sign ?

95. Nnesha

i mean degree how did you put little 0 ? :P

96. anonymous

I did option shift and then 8

97. Nnesha

maybe they just want us to write the number like 28 and 62

98. anonymous

I tried that but it was incorrect I think they want me to show that it's degrees

99. Nnesha

ye answer is right but syntax incomplete  :.........

100. anonymous

-,-

101. Nnesha

sorry don't know i do it b hand so

102. anonymous

I just emailed my instructor hopeful he responds:) thanks again so much for all your help

103. Nnesha

oh okay please let me know what was the mistake :=)

104. Nnesha

it was pleasure :=)

105. Nnesha

good work!

106. anonymous

:) I think it's just something that has to do with the keys I don't think it's the actual math

107. Nnesha

ye right :=)

108. anonymous

:D

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