а)(8х-5)+(3х-7)-(9х-11)=8x-5+3x-7-9x+11=2x-1
б)43х-19у-(15х-34у)+(9х-7у)=43x-19y-15x+34y+9x-7y=37x+8y
в)48а-(2а-2b)-(14b-28a)+(24b-18a)=48a-2a+2b-14b+28a+24b-18a=56a+12b
a)12ab-30bc-3cx-(15bc+9cx)=12ab-30bc-3cx-15bc-9cx=12ab-45bc-12cx
b)(10abc-8bcx-21cxy)-(-6abc+bcx-cxy)=10abc-8bcx-21cxy+6abc-bcx+cxy=16abc-9bcx-20cxy