Решите уравнение .. 5/8×1 3/7×(-0,7х)=5,2

5/8 • 1 3/7 • ( - 0,7х ) = 5,2
5/8 • 10/7 • ( - 0,7х ) = 5,2
25/28 • ( - 0,7х ) = 26/5
- 0,7х = 26/5 : 25/28
- 7/10х = 728/125
- х = 728/125 : 7/10
- x = 7280/875
x = - 8,32