Answer:
first one : inscribed angles create arc twice their degree
so, 115° created a 230 ° arc
360 - 230 = 130°
that means ∠EDG = 1/2 (130) or 65°
second : ∠ABD = 180 - 112 = 68
The arc created APD is 2 times ∠ABD or 136°, therefore ∠x = 136°.
Central Angles and arcs are equal
360° - 136° = 224°
224° is the arc created by ∠APD. Take 1/2 of 224° and you get 112°
Third: ∠ACB and ∠ AOB create the same arc.
since ∠ACB is 48°, the arc is 96° (twice the angle)
if the arc is 98° then the central angle ∠AOB = 98°
360°-98° = 262°
You need this because ∠APB is 1/2(262-98) or 82°
Fourth : Both inscribed angles create the same arc
so the angles are equal
∠DEG = 38°
