Answer:
For the first one it is D.
Step-by-step explanation:
I added 84.6 and 30.4 which gives me 115. I then added 66 to get 181, triangles angles only add up to 180 degrees, therefore they are not similar.
Answer:
-18
Step-by-step explanation:
Left Hand Side = -2(7a + 9b) = -14a - 18b
Comparing it with Right Hand Side, ? = -18
Answer: C
Step-by-step explanation:
We know that
, and thus by the exterior angle theorem,

Thus, 
Answer:
2x-5
Step-by-step explanation:
6x-5-4x
2x-5