Ответ:

1) 8(0,7x-4)-2(0,2x-3)=-39

5,6x-32-0,4x+6=-39

5,2x=-13

x=2,5

2) 41,4(14/23x+5/9)-79,8(8/19x-5/6)=76,9

207/5(14/23x+5/9)-399/5(8/19x-5/6)=769/10

126/5x+23-168/5x +133/2=769/10

126/5x+179/2-168/5x=769/10 | * 10

252x+895-336x=769

-84x=769-895

x=3/2=1,5