-1300 bn à

hình như mik cũng có 1 người bn cũng tên là nguyen ha giang lun đó bn đó hc cũng giỏi lắm

  13(26-58)-26(13+21)
=13.26-13.58-26.13+26.21
=13.26-26.13-13.58+26.21
=0-13.58+26.21
=0-2.(13.29+13.21)
=0-2.[13.(29+21)]
=0-2.(13.50)
=0-2.650
=0-1300
=-1300

sai em nhé 

đúng nhé 

\(\dfrac{13}{26}=\dfrac{13:13}{26:13}=\dfrac{1}{2}nhé\)

= \(\frac{13}{45}x\left(\frac{15}{26}-1\frac{1}{26}+\frac{11}{26}\right)=\frac{13}{45}x\left(\frac{15}{26}-\frac{27}{26}+\frac{11}{26}\right)=\frac{13}{45}x\left(\frac{27}{26}-\frac{27}{26}\right)=\frac{13}{45}x0=0\)

=25/26

25/26

25/26

\(\frac{x}{13}+\frac{15}{26}=\frac{23}{26}\)

\(\Leftrightarrow\frac{x}{13}=\frac{8}{26}\)

\(\Leftrightarrow\frac{x}{13}=\frac{4}{13}\)

\(\Leftrightarrow x=4\)

\(\frac{x}{13}+\frac{15}{26}=\frac{23}{26}\)

\(\Leftrightarrow\frac{x}{13}=\frac{23}{26}-\frac{15}{26}\)

\(\Leftrightarrow\frac{x}{13}=\frac{8}{26}\)

\(\Leftrightarrow\frac{2x}{26}=\frac{8}{26}\)

\(\Leftrightarrow2x=8\)

\(\Leftrightarrow x=8:2\)

\(\Leftrightarrow x=4\)

Ko ghi lại đề bài:

\(=>\frac{x}{13}=\frac{8}{26}\)

\(=>\frac{x}{13}=\frac{4}{13}\)

\(=>x=4\)

=76 804

26 x 8 + 4 x 13 - 10 x 26 

= 26 x 8 + 2 x 2 x 13 - 10 x 26 

= 26 x 8 + 2 x 26 - 10 x 26 

= 26 x ( 8 + 2 - 10 ) 

= 26 x 0 

= 0 

Chúc bạn học tốt !!! 

= 26 x 8 + 2 x 26 - 10 x 26

= 26 x ( 8 + 2 - 10 )

= 26 x 0

= 0

(13-135+49)-(13+49)

= 13-135 + 49 - 13-49

= ( 13-13) + ( 49-49) -135

= 0 -135

=-135

26.(24-11)-24.(26-11)

= 26.24 - 11.26 - 24.26 - 11.24

= 24.(26-26) -11(26-24)

= 0 - 11.2

=-22

\(\left(13-135+49\right)-\left(13+49\right)\))

\(=13-135+49-13-49\)

\(=\left(13-13\right)+\left(49-49\right)-135\)

\(=0-135=-135\)

\(26.\left(24-11\right)-24.\left(26-11\right)\)

\(=26.24-11.26-24.26-11.24\)

\(=24.\left(26-26\right)-11.\left(26-24\right)\)

\(=0-11.2=-22\)

B

B

B

   26 × 8 + 4 × 13 - 10 × 26

= 26 x 8 + 2 x ( 2 x 13 ) - 10 x 26

= 26 x 8 + 2 x 26 - 10 x 26

= 26 x ( 8 + 2 - 10 )

= 26 x 0

= 0

\(26\times8+4\times13-10\times26\)

\(=13\times2\times2\times4+4\times13-10\times2\times13\)

\(=13\times4\times4+4\times13-20\times13\)

\(=13\times4\times4+4\times13-4\times5\times13\)

\(=13\times4\times\left(4+1-5\right)\)

\(=13\times4\times0\)

\(=0\)

Chúc bn học tốt !!!

\(26\times8+4\times13-10\times26\)

\(=26\times8+2\times2\times13-10\times26\)

\(=26\times\left(8+2-10\right)\)

\(=26\times0\)

\(=0\)