Đáp án:
a, 9,6 + y : 3,2 = 12,12.
=> y:3,2= 12,12-9,6
=> y:3,2=2,52
=> y= 2,52 x 3,2
=> y= 8,064
b, ( 14 - y : 6 ) x 7 = 84.
=> 14-y:6=84:7
=> 14-y:6=12
=> y:6=14-12
=> y:6=2
=> y=2 x 6
=> y=12
c, 3/4 × y : 1/2 = 4/5
=> y:1/2= 4/5 : 3/4
=> y:1/2=16/15
=> y=16/15 x 1/2
=> y= 8/15
BẠN THAM KHẢO NHA!!!