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arc BC = 60°m∠ADC = 60°m∠AEB = 105°m∠ADP = 45°m∠P = 60°
Step-by-step explanation:
The sum of arcs of a circle is 360°. The given conditions tell us arc BC ≅ arc AB, so the four arcs of the circle have ratios ...
CB : BA : AD : DC = 2 : 2 : 3 : 5
The sum of ratio units is 2+2+3+5 = 12, so each one stands for 360°/12 = 30°. Then the arc lengths are ...
arc BC = arc BA = 60° . . . . 2 ratio units each
arc AD = 90° . . . . . . . . . . . . 3 ratio units
arc DC = 150° . . . . . . . . . . . .5 ratio units
The inscribed angles are half the measure of the intercepted arcs:
∠ADC = (1/2) arc AC = 1/2(120°) = 60°
∠ADP = 1/2 arc AD = 1/2(90°) = 45°
The angles at E are half the sum of the measures of the intercepted arcs.
∠AEB = (arc AB + arc CD)/2 = (60° +150°)/2 = 105°
Angle P is half the difference of the intercepted arcs.
∠P = (arc BD -arc AD)/2 = (210° -90°)/2 = 120°/2 = 60°
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In summary, ...
arc BC = 60°
m∠ADC = 60°
m∠AEB = 105°
m∠ADP = 45°
m∠P = 60°
