Câu trả lời:

b)/1/2x-1/3/-150%=(-1/2)^2

/1/2x-1/3/-3/2=1/4

/1/2x-1/3/=1/4+3/2

/1/2x-1/3/=7/4

/1/2x/=7/4+1/3

/1/2x/=25/12

x=25/12:1/2

x=25

c)2x:7/4=35%:(-1 2/3)^2

2x:7/4=7/20:25/9

2x:7/4=63/500

2x=63/500.7/4

2x=441/2000

x=441/2000:2

x=441/4000