## anonymous one year ago Suppose a triangle has two sides of length 42 and 35, and that the angle between these two sides is 120. What is the length of the third side of the triangle?

1. anonymous

2. anonymous

3. anonymous

can you help?

4. anonymous

hey m8

5. anonymous

hmm i will try

6. anonymous

7. arindameducationusc

I am trying too...

8. anonymous

Thank you both.

9. anonymous

I am like stressing because of this test I cant pass

10. anonymous

ok so you use the law of cosine i think

11. anonymous

yea I did but I got lost after

12. anonymous

$c^2=a^2+b^2$

13. anonymous

oh i forgot the -2abcos(o)

14. anonymous

anyways $c^2=32^2+35^2−2(32)(35)\cos(120)$

15. arindameducationusc

cos A=b^2+c^2-c^2/2ab This is the cosine formula, Isn't it? @Icedragon50

16. anonymous

where did you get 32?

17. anonymous

$c^2=1024+1225-2240(-\frac{ 1 }{ 2 })=3369$

18. anonymous

c=$√3369=58.04$

19. anonymous

and there ya go!

20. anonymous

@arindameducationusc ya

21. anonymous

Thank you so much m8

22. anonymous

np :)

23. anonymous

g'night I'm tired xD

24. anonymous

Same its 1 lol

25. anonymous

bout to play league of legends