k minh minh giai

* (-6 - 2) . (-6 + 2)

=    -8   .     -4

=           32

*(7 . 3 - 3) : (-6)

=      18    : (-6)

=            -3

k cho mik nhe

=73 nha bạn

73 cậu nha

\(\frac{18}{27}-\frac26\)

\(=\frac23-\frac13=\frac{2-1}{3}=\frac13\)

\(\frac{37}{12}-3=\frac{37}{12}-\frac{36}{12}=\frac{37-36}{12}=\frac{1}{12}\)

\(5-\frac{14}{3}=\frac{15}{3}-\frac{14}{3}=\frac{15-14}{3}=\frac13\)

\(\frac{10}{21}:\frac23=\frac{10}{21}\times\frac32=\frac{30}{42}=\frac57\)

\(\frac35:\frac34=\frac35\times\frac43=\frac33\times\frac45=\frac45\)

\(\frac25:\frac{3}{10}=\frac25\times\frac{10}{3}=\frac{20}{15}=\frac43\)

\(\frac38:\frac94=\frac38\times\frac49=\frac{12}{72}=\frac16\)

\(\frac{8}{21}:\frac47=\frac{8}{21}\times\frac74=\frac{7}{21}\times\frac84=\frac23\)

\(\frac85:\frac{15}{8}=\frac85\times\frac{8}{15}=\frac{64}{75}\)

1=32

2=-3

3=-16

4=-9

5=0

6=6

7=1

8=25

nhớ tick cho mình nha

sai hết Le Truong Yen Khoa

(1+x)+(2+x)+(3+x)+(4+x)+(5+x)=10*5

(1+2+3+4+5)+ (x+x+x+x+x)=50

15+5*x=50

5*x=50-15

5*x=35

x=35:5=7

(1+x)+(2+x)+(3+x)+(4+x)+(5+x)=10*5

1+x+2+x+3+x+4+x+5+x=50

(1+2+3+4+5)+(x+x+x+x+x)=50

15+5x=50

5x=50-15

5x=35

x=35:5

x=7

a) \(\dfrac{3}{8}+\dfrac{15}{-25}+\dfrac{3}{5}\)

\(=\dfrac{-9}{40}+\dfrac{3}{5}\)

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

b) \(\dfrac{-5}{18}+\dfrac{23}{45}-\dfrac{9}{10}\)

\(=\dfrac{7}{30}-\dfrac{9}{10}\)

\(=\dfrac{-2}{3}\)

c) \(\dfrac{-5}{12}+\dfrac{15}{18}-2,25\)

\(=\dfrac{5}{12}-2,25\)

\(=\dfrac{-11}{6}\)

d) \(\dfrac{5}{6}+\dfrac{2}{3}-0,5\)

\(=\dfrac{3}{2}-0,5\)

\(=1\)

tick cho mink nhé bn ✔

sử dung kết hop

Câu b:

1/5 : 1/10 - 1/3.(6/5 - 9/4)

= 1/5 x 10 - 1/3.(24/20 - 45/20)

= 2 - 1/3.(-21/20)

= 2 + 7/20

= 40/20 + 7/20

= 47/20

1+1=2

a) 15 x 21 - 16 : 4 + 7 

=    315    -      4    + 7

=           311   +     7

=             318

b) 123 - 11 x 6 + 150 : 30

=  123 -    66    +      5

=      57      +     5

=        62

Mình chỉ làm đến đó thôi chứ mấy câu còn lại khó hiểu quá!Ở lớp 5 mình chưa học bao giờ.

a)

=315-4+7=318

b)

=123-66+5=62

c)

=2017+5x[300-700:7]

=2017+5x[300-100]

=2017+5x200

=2017+1000

=3017

d)

=1560:[5x79-370+5x21]

=1560:[395-370+105]

=1560:130

=12

e)

=50-[12:2+34]

=50-40

=10

g)

=10-[16x5+88]:28

=10-168:28

=10-6

=4