Đáp án:
A, x-25/6=-11/3+7/2
x-25/6= -1/6
x = -1/6+25/6
x = 4
B, 3 1/3x-20/3=4/5-2 1/12
10/3x-20/3=4/5-14/12
10/3x-20/3= -11/30
10/3x = -11/30-20/3
10/3x = -211/30
x = -211/30 :10/3
x = -211/100
C, (x+-2/5):2 3/4-0,8=-3/2
(x+-2/5):11/4-4/5=-3/2
(x+-2/5): 39/20 =-3/2
(x+-2/5) =-3/2x39/20
x+-2/5 = 13/10
x = 13/10--2/5
x = 17/10
B, (3,5-x).2 1/5-50%=2 7/10
(7/2-x).11/5-1/2=27/10
(7/2-x). 17/10= 27/10
(7/2-x) = 27/10:17/10
7/2-x = 27/17
x = 7/2-27/17
x = 65/34
