Помогите с 1 и 2 задание

Question

Помогите с 1 и 2 задание

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Answer 1

1. BC=AB-AC=7-5=5cm
2. AOC=COB+30
COB+(COB+30)=120
2COB=90
COB=45
AOC=45+30=75
3. AOB=64, AOC=AOB/2=32

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