Answer:
Full proof below
Step-by-step explanation:

Answer:
10.3 units
Step-by-step explanation:
Recall: SOHCAHTOA
Reference angle = 69°
Side length Opposite to reference angle = x
Hypotenuse length = 11
Thus, apply the trigonometric ratio, SOH:
Sin 69 = Opp/Hyp
Substitute
Sin 69 = x/11
11 × Sin 69 = x
10.2693847 = x
x = 10.3 units (nearest tenth)
X=40 degrees because it s on the circle. arc AD+arc DC=180 arc DC is 100 so AD is 80. That means x must be 40.