Hello!
Let's take this problem in steps
First image
--> angle A = 30 degrees
--> length of a = 6
==> using trigonometry, the relationship between side opposite angle
A and the hypotenuse is:

Second image
--> angle A = 21 degrees
--> length of c = 8
==> using trigonometry, the relationship between the side opposite
angle A and the hypotenuse is:

Third image:
--> angle A = 55 degrees
--> length of C = 8
==> using trigonometry, the relationship between the side adjacent
angle A and the hypotenuse is:

Answer
- First Image: 12
- Second Image: 2.9
- Third Image: 4.6