Упростите выражения 2/7 (1,4a-3 1/2b) - 1,2 (5/6a-0,5b)

2/7 (1,4a-3 1/2b) - 1,2 (5/6a-0,5b) = 2/7*1,4a-2/7*3 1/2b-1.2*5/6a-1.2 * (-0.5b) =

= 2/7*1 4/10a-2/7*7/2b-1 2/10*5/6a-1 2/10 * (-5/10b) =

=2/7*14/10a-b-12/10*5/6a-12/10 * (-5/10b) = 2/5a-b-a+3/5b=

=2/5a-5/5b-5/5a+3/5b=-3/5a-2/5b