Помогите. Номер 673, задание б

Question

Помогите. Номер 673, задание б

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Answer 1

1) x + 50 = 180

x = 130

x = AOB

2)x + 20 + x = 180

2x = 160

x = 80

x = AOB

3)X + 4X = 180

5X = 180

X = 36

4X = 144

4x = AOB

4)3X + 2X = 180

5X = 180

X = 36

3*36 = 108

108 = AOB

5)BOC = AOB-30

AOB = X

x-30 + x = 180

2x = 150

x = 75

x = AOB