=-1+1-0,5=-0,5
..................... Ответ:б
х+5у=35,3х+2у=27
x=35-5y
3(35-5y)+2y=27
-15y+2y=27-105
-13y=-78
y=6
x=35-5*6=35-30=5
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(m+2n)^3=m^3+6m^2n+6mn^2+2n^3