Answer:
A
Step-by-step explanation:
Answer:
-9
Step-by-step explanation:
- 2 + ( - 7 )
- 2 - 7 = -9 ( Answer)
Well, you have to do it with the substitution method now it's not easy, it takes some time to get used to it. I'm not really sure how to explain it but if you go on Khan Academy it will show you how to do it.
Step-by-step explanation:
here,,
a=3,b=10,C=120°
c^2=a^2+b^2-2ab cos120°
=(3)^2 +(10)^2 _2 (3)(10)(-1/2) [cos120°=-1/2]
=9+100-(-30)
=109+30
=139
c=(139 )1/2=11.79
c=12
