3(a+2b)-a при a+3b=1.1 2.4(3x+5y)-4y при 0.9x+y=2 8(0.5a+3b)+8a при a+2b=2.5 3(0.6m+5n)-3n при 0.3m+2n=4

3(a+2b)-a=3а+6b-a=2a+6b=2(a+3b)=2*1.1=2.2 
2.4(3x+5y)-4y=7.2x+12y-4y=7.2x+8y=8(0.9x+y)=8*2=16
8(0.5a+3b)+8a=4a+24b+8a=12a+24b=12(a+2b)=12*2.5=30
3(0.6m+5n)-3n=1.8m+15n-3n=1.8m+12n=6(0.3m+2n)=6*4=24