Выражения а) 2(6+n)-3(2m-n) б) 12,3-2c-8-24,7(7-3c)

2(6+n) - 3 (2m-n)= 12+2n-(6m-3n)=12+2n-6m+3n=
=12 -6m+5n= 6(2-m)+5n

12.3 -2c -8 -24.7 (7-3c) = 14.3-2c - (172.9-74.1c) =
=14.3-172.9+74.1c= -158.6 +74.1c = 13 (5.7c -12.2)

A) 12+2n-6m+3n=12+5n-6m
б) 12.3-2c-8-172.9+74.1=86.4-2c-180.9=-93.5-2c