Помогите с 45 все..................

Question

Помогите с 45 все..................

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Answer 1

1)a-4a+11+9-2a=20-5a
20-5a=20-5a

2)18b-24-15b+55+2=3b+33
3b+33=3b+33

3)10-9c+6+7c-16=-2c
-2c=-2c