Ответ:

3(2а+b-8с)=3×2а+3b-3×8с=6а+3b-24с

-4(-х+3у-4z)=-4×(-х)-4×3у-4×(-4z)=4х-12у+16z

4х-13х+29х-14х=(4-13+29-14)х=6х

2,3а+1,8-3,2а-2,4=-0,9а+1,8-2,4=-0,9а-0,6

2,5(4а-8b)-(3а-4b)×1,4=10а-20b-(4,2а-5,6b)=10a-20b-4,2a+5,6b=5,8a-14,4b

9/16(5 1/3x- 2/3y)- 7/20(2 6/7x- 5 5/7y)= 9/16(16/3x-2/3y)-7/20(20/7x-40/7y)=3x-3/8y-x+2y=2x+13/8y