1)9*(7х-6)-18х=63x-54-18x=45x-54
2)7а-6*(19-а)=7a-114+6a=13a-114
3)0,8*(6х-2)+1,6*(х-4)=4,8x-1,6+1,6x-6,4=6,4x-8
4)2,8*(5b-6а)-(7b-8а)-1,2=14b-16,8a-7b+8a=7b-8,8a
5)-(-4,9-5,8к)-(3,1к-5,6)=4,9+5,8k-3,1k+5,6=10,5+2,7k
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