Answer:

Step-by-step explanation:
we know that
The formula of law of cosines is equal to

where
a, b and c are sides. C is the angle opposite side c
In this problem we have

substitute the given values






Answer:
Step-by-step explanation:
Here you go mate
Step 1
(-5)(5) +5 Equation
Step 2
(-5)(5) +5 Simplify
(-5)(5) +5
Step 3
(-5)(5) +5 Add and multiply them
(-25)+5
answer
-20
I hope you meant find x
5x + 3x + 2x = 180. x=18
For the first triangle, I believe the given angles are 85 and 53. If I am incorrect, please let me know and I'll resolve it.
The answer for 1 would be 42.
2nd triangle- 69 is the missing angle measurement.
3rd- 64 degrees.
4th- 53
The reasoning behind all of these: The total of all three interior angles should be 180 degrees. So when you add the two GIVEN angles, and subtract that from 180, this answer is your missing angle.
(Also, for any other site or anything, it might be best to block out your name)