Đáp án:
Giải thích các bước giải
A=( -3/4+-1/4) +(2/7+5/7)+3/5=-1+1
+3/5=0+3/5=3/5
B=1
C=3/5:12/25=3/5.25/12=3.5.5/5.3.4=5/4
D=5/6x-3/4=-5/8
e,1/7+-4/7=-3/7
f,3/5 .5/6=18/30-25/30=-7/30
g,-8/3 .15/24=-8/3.5/8=-5/3
h,5/9:5/-3=5/9 .-3/5=-1/3
2,
x . 2/5=1/10 x :-2/5 =4/10
x =1/10:2/5 x =4/10 . -2/5
x =1/4 x =-4/25
Vậy x = 1/4 Vẫy =-4/25
x -3/4=-2/5 x .3/8 =1/4
x =-2/5+3/4 x =1/4:3/8
x =7/20 x =2/3