-x-2/3=-6/7

-x = -6/7 + 2/3

-x = -4/21

Vậy x = -4/21

-x-2/3=-6/7

<=>-x=2/3-6/7

<=>x=4/21

\(-x-\frac{2}{3}=-\frac{6}{7}\)

\(-x=-\frac{6}{7}+\frac{2}{3}\)

\(-x=\frac{-18}{21}+\frac{14}{21}\)

\(-x=\frac{-4}{21}\)

\(\Rightarrow x=\frac{4}{21}\)

Vậy \(x=\frac{4}{21}\)

| x+1| +5 = 2

|x+1| = 2-5

| x+ 1| = -3 ( Vô Lí)

=> \(x\in\left\{\varnothing\right\}\)

\(=\dfrac{2^{18}\cdot3^{14}\cdot3^3\cdot2^7+3^{15}\cdot2^{15}}{2^{10}\cdot2^{15}\cdot3^{15}+3^{14}\cdot3\cdot5\cdot2^{26}}\)

\(=\dfrac{2^{25}\cdot3^{17}+3^{15}\cdot2^{15}}{2^{25}\cdot3^{15}+3^{15}\cdot5\cdot2^{26}}\)

\(=\dfrac{2^{15}\cdot3^{15}\left(2^{10}\cdot3^2+1\right)}{2^{25}\cdot3^{15}\left(1+5\cdot2\right)}=\dfrac{1}{1024}\cdot\dfrac{9217}{11}=\dfrac{9217}{11264}\)

tk

thực hiện phép tính;        a.\(\frac{2^{18}.18^7.3^3+3^{15}.2^{15}}{2^{10}.6^{15}+3^{14}.15.4^{13}}\) - Hoc24

12+30=42

90-30=60

100-18=82

12+30=43

90 - 30 = 60

100 - 18 = 82

đổi tk ko

42, 60, 82

Bài 1 : 

a, 5/7 - 3/6 + 2/7 + 9/6 - 4/3 - 1/3 

= (5/7 + 2/7) + (9/6 - 3/6) - (4/3 + 1/3)

= 1 + 1 - 5/3

= 2- 5/3

= 1/3

b. 0,75 + 5,64 + ( 7,25 - 3,14 )

= (0,75 + 7,25) + (5,64 - 3,14)

= 8 + 2,5

= 10,5

c, 15/26 x 39/25 x 54/18 x 36/27 ( Làm = cách triệt tiêu )

\(=\frac{15\cdot39\cdot54\cdot36}{26\cdot25\cdot18\cdot27}\)

\(=\frac{3\cdot5\cdot3\cdot13\cdot27\cdot2\cdot2\cdot18}{2\cdot13\cdot5\cdot5\cdot18\cdot27}\)

 
\(=\frac{3\cdot3\cdot2}{5}\)

\(=\frac{18}{5}\)
Bài 2 : Tìm x 

a, ( 6,73 + 5,26 - 3,5 ) - x = 4,32 - 2,56 

8,49 - x = 1,76

x= 8,49 - 1,76

x= 6,73

b, x : (  7,25 - 5,42 ) = 4,63 +1,37 

x : 1,83 = 6

x= 6 * 1,83 

x= 10,98

Mary is having lunch in a restaurant with her friends at the moment

Mary are having lunch with her friends in a restaurant at the moment.

Mary is having lunch with her friends in a restaurant at the moment