Answer:
A, C
Step-by-step explanation:
Actually, those questions require us to develop those equations to derive into trigonometrical equations so that we can unveil them or not. Doing it only two alternatives, the other ones will not result in Trigonometrical Identities.
Examining
A) True

Double angle 
B) False,
No further development towards a Trig Identity
C) True
Double Angle Sine Formula 

D) False No further development towards a Trig Identity
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Answer:

Step-by-step explanation:
∠ABD is the sum of the angles ∠ABC and ∠CBD. In other words:

Substitute in known values:

And subtract. Hence:

In conclusion, ∠ABC measures 34°.
The sum that represents the number of tickets sold if 35 tickets were sold Monday, half of the remaining tickets were sold on Tuesday and 14 tickets were sold on Wednesday.
To start solving this, we can assign t as the variable to the total number of tickets that were sold. So, t = 35 (for Monday) + (t - 35)/2 (for Tuesday) + 14 (for Wednesday). To solve this, we can say t = 49 + (t - 35)/2, or 2t = 98 + t - 35, which equals t = 63. Therefore, 63 tickets were sold total.
Changing the subject of the formula
Answer:
2 3 1 3
Step-by-step explanation: