РЕШИ УРАВНЕНИЯ: б) 5 3/7-(b-2 1/7)=2 4/7; а) (4 1/9-а )+8 5/9=9 2/9;

5 ( 3/7 ) - ( b - 2 ( 1/7 )) = 2 ( 4/7 )
5 ( 3/7 ) - b + 2 ( 1/7 ) = 2 ( 4/7 )
7 ( 4/7 ) - 2 ( 4/7 ) = b
B = 5
Ответ b = 5
( 4 ( 1/9 ) - a ) ) + 8 ( 5/9 ) = 9 ( 2/9 )
12 ( 6/9 ) - a = 9 ( 2/9 )
A = 12 ( 6/9 ) - 9 ( 2/9 )
A = 3 ( 4/9 )