Answer:
b. 44°
Step-by-step explanation:
Reference angle = x
Hypotenuse = 21
Adjacent = 15
Apply trigonometric function CAH:



x = 44.4153086° ≈ 44° (nearest degree)
Answer:
There are 180 degress in a triangle. so minus the angles given from 180 to find X.
X = 180 - 106 - 30
X = 44 degrees
Sin(2π/3radians) = sin(π/3radians) = (<span><span>√3)/</span>2</span>cos(2π/3radians) =<span> - cos(π/3radians) = 1/2
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becuase 2π/3 + π/3 = <span>π</span>