Let's simplify the equation step by step:

6.4(2-3у) = 6(0.8у-1) + 6.8

First, distribute the 6.4 on the left side and 6 on the right side:

12.8 - 19.2у = 4.8у - 6 + 6.8

Combine like terms:

12.8 - 19.2у = 4.8у + 0.8

Next, move all the y terms to one side and the constants to the other side:

-19.2у - 4.8y = 0.8 - 12.8

-24у = -12

Now, divide by -24 to solve for y:

y = -12 / -24
y = 0.5

So the solution to the equation is y = 0.5.