## anonymous one year ago Two triangles can be formed with the given information. Use the Law of Sines to solve the triangles. B = 46°, a = 12, b = 11 A = 38.3°, C = 95.7°, c = 8; A = 141.7°, C = 84.3°, c = 8 A = 51.7°, C = 82.3°, c = 8; A = 128.3°, C = 5.7°, c = 8 A = 38.3°, C = 95.7°, c = 15.2; A = 141.7°, C = 84.3°, c = 15.2 A = 51.7°, C = 82.3°, c = 15.2; A = 128.3°, C = 5.7°, c = 1.5 @ganeshie8 @dan815 @pooja195 @nincompoop @hero @wio @luigi0210 @.sam. @usukidoll

1. butterflydreamer

do you know your sine rule? :)

2. anonymous

no i dont know anything

3. anonymous

do u know the answer? @butterflydreamer

4. butterflydreamer

|dw:1436242601937:dw|

5. butterflydreamer

lmaooo i'm not here to give you a direct answer. It's against CoC... :)

6. anonymous

well i dont want the answer but i want the step by step

7. anonymous

cuz i have no clue how to do this

8. butterflydreamer

that's fine :) Anyway, so the sine rule basically is this: $\frac{ a }{ sinA } = \frac{ b }{ sinB} = \frac{ c }{ sinC}$ and you can even flip it around: $\frac{ sinA }{ a } = \frac{ sinB }{ b}= \frac{ sinC }{ c }$ Now you want to draw up a triangle and label the information give to you which is: B = 46 , a = 12, b = 11 so, |dw:1436242931550:dw| Firstly, we want to find angle A

9. anonymous

okay so what do we do next?

10. butterflydreamer

Using the sine rule we can find angle A like this : $\frac{ sinA }{ a } = \frac{ sinB }{ b } \rightarrow \frac{ sinA }{ 12 } = \frac{ \sin46 }{ 11 }$

11. butterflydreamer

|dw:1436243178342:dw|

12. butterflydreamer

now to find A we go: |dw:1436243370517:dw|

13. anonymous

i got an error sign @butterflydreamer

14. butterflydreamer

did you plug it into the calculator correctly? Try again Lol. I plugged it into my calculator and got a number so you should get one too :)

15. anonymous

i got none of my option? can u tell me what it is @butterflydreamer

16. anonymous

17. anonymous

i give up @butterflydreamer can u please just tell me :)

18. anonymous

19. butterflydreamer

http://prntscr.com/7pq08q round that number to 1 decimal place

20. anonymous

okay thats 5.7 but that only A it only narrows our options to two

21. anonymous

51.7

22. anonymous

A = 51.7°, C = 82.3°, c = 8; A = 128.3°, C = 5.7°, c = 8 A = 51.7°, C = 82.3°, c = 15.2; A = 128.3°, C = 5.7°, c = 1.5 so which one of these are the answers? @butterflydreamer

23. butterflydreamer

yeeep so A = 51.7 Now use the sine rule and follow a similar method to solve for c and C

24. anonymous

so can u help me solve them please :)

25. butterflydreamer

|dw:1436244696917:dw| Find angle C by using the fact that the angle sum (all 3 angles in a triangle) = 180. So we have two angles right? A = 51.7 , B = 46. Therefore C = 180 - 51.7 - 46 = ?

26. anonymous

82.3

27. anonymous

i need help finding little c

28. butterflydreamer

yeep C = 82.3 Now to find the length of c, we need to use the sine rule again: |dw:1436244903292:dw| |dw:1436244943797:dw|