giúp mình đi mọi người T.T

a) x = 6/5 - 5/6

    x =  11/30

vậy x =...

b) x = 13/4 - 3/5 

    x = 53/20

vậy x =...

A

A

\(=\dfrac{10}{8};\dfrac{3}{8}\)

\(=\dfrac{36}{30};\dfrac{25}{30}\)

\(=\dfrac{65}{20};\dfrac{12}{20}\)

chi tiết đi được ko bạn, nhân cho mấy

C

c

a: \(x\ge1\frac15\)

=>\(x-1\frac15>0;x-\frac15>0\)

=>\(M=x-1\frac15+x-\frac15-3\frac15=2x-\frac65-\frac15-\frac{16}{5}=2x-\frac{23}{5}\)

b: \(x\le\frac15\)

=>\(x-\frac15\le0\)

=>\(x-\frac15-1\le-1<0\)

=>\(x-1\frac15<0\)

Ta có: \(M=\left|1\frac15-x\right|+\left|x-\frac15\right|-3\frac15\)

\(=\frac65-x+\frac15-x-\frac{16}{5}=\frac{-9}{5}-2x\)

c: \(\frac15

=>\(x-\frac15>0;x-\frac65<0\)

Ta có: \(M=\left|1\frac15-x\right|+\left|x-\frac15\right|-3\frac15\)

\(=\frac65-x+x-\frac15-3-\frac15=1-3-\frac15=-2-\frac15=-\frac{11}{5}\)

Giúp mình vs ạ. Cần gấp

\(\dfrac{3}{4}\)+\(\dfrac{1}{4}\): x=\(\dfrac{-2}{5}\)

⇒\(\dfrac{1}{4}\):x=\(\dfrac{-2}{5}\)-\(\dfrac{3}{4}\)

⇒ x=\(\dfrac{1}{4}\): \(\dfrac{-23}{20}\)

⇒ x=\(\dfrac{-5}{23}\)

Giải:

B=1,4 .15/49 - (4/5+2/3) :2 1/5

B=7/5.15/49 - 22/15 : 11/5

B=3/7 - 2/3

B=-5/21

Chúc bạn học tốt!

thanks nha! 

mình cũng chúc bạn học tốt

77/45

7/6

29/10

\(\dfrac{3}{5}+\dfrac{4}{3}\times\dfrac{5}{6}=\dfrac{3}{5}+\dfrac{10}{9}=\dfrac{27}{45}+\dfrac{50}{45}=\dfrac{77}{45}\)

\(2-\dfrac{7}{6}+\dfrac{1}{3}=\dfrac{12}{6}-\dfrac{7}{6}+\dfrac{2}{6}=\dfrac{7}{6}\)

\(\dfrac{7}{6}\times3-\dfrac{3}{5}=\dfrac{7}{2}-\dfrac{3}{5}=\dfrac{35}{10}-\dfrac{6}{10}=\dfrac{29}{10}\)

Sửa đề: A=5/2+5/6+...+5/2450

=5(1/2+1/6+...+1/2450)

=5(1-1/2+1/2-1/3+...+1/49-1/50)

=5*49/50<5