Помогите!!!!?!!!!!!!

Question

Помогите!!!!?!!!!!!!

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Answer 1

1) 66 - 85/180 : 19/45
(- 19/180) : 19/45
- 19/180 * 45/19
= - 1/4
- 0/25

4) 21 * 3 - 21 х/7 = 21 * х/3

63 - 3х = 7х

- 3х - 7 х = - 63

- 10х = -63

х = 63/10 или х = 6 3/10 , или х = 6,3