In pentagon ABCDE, \overline{AC} bisects \angle BCE and ¯AD bisects ∠BDE. If ∠CBD=30∘ and ∠CED=60∘, then find ∠CAD, in degrees.
Find ∠CAD in degrees.
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∠ADB=∠ADE=α∠ACB=∠ACE=β
The angles intersection AD/EC are twice:
(120°−α) and (60°+α)
The angles intersection AC/BD are twice:
(30°+β) and (150°−β)∠CAD=60°+α−β
In the triangle (intersection AC/BD) - A-D the following applies:
α=180°−(150°−β)−(60°+α−β)β=15°
The angles intersection BD/CE are twice:
(180°−30°−2β=120°) and (60°)
In the triangle (intersection AD/CE) - (intersection CE/BD) - D the following applies:
(120°)+(60°+α)+(α)=180°α=0 ? ? ?
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