Решите уравнение 5/7(5,6-2,1y)=2,4(5/8-2/3y)

5/7( 5,6 - 2,1у ) = 2,4( 5/8 - 2/3у )
5/7( 28/5 - 21/10у ) = 12/5( 5/8 - 2/3у )
28/7 - 3/2у = 3/2 - 8/5у
3/2у - 8/5у = 28/7 - 3/2
( 15у - 16у ) / 10 = ( 56 - 21 ) / 14
14 • ( - у ) = 10 • 35
- 14у = 350
у = - 25