I believe it is -20.
Hope that helped you out.
Answer:

Step-by-step explanation:
using the cosine ratio;

From the question, the side of the right angle triangle that is adjacent to the measured <a,(i.e BAC) is AC=24 and the hypotenuse is AB=25
This implies that,

Answer:
A,B,D
Step-by-step explanation:
By replacing the points in the current equation you can get true statements which are correspondent to answer A,B,D
The answer is A) 3.
I hope this helps.