a) 290                  

b) 180                  

c) 200                  

d) 100

= 26 . ( 13 + 7 ) - 17 . ( 9 + 11 )

= 26 .      20      - 17 .     20

= 20 . ( 26 - 17 )

= 20 .       9

=     180

b)

= ( 35 . [ 23 + 37 ] ) : 60

= ( 35 .      50       ) : 60

=         175            : 60

=                \(\frac{175}{60}\)

c)

= ( 257 . [ 139 - 39 ] ) : 100

= ( 257 .      100      ) : 100

=                 257

26.7-17.9+13.26-17.11=180

2con kia bạn lên xem lại đề bài

\(\dfrac{35.9-7.3}{17.5+17.11}=\dfrac{7.5.3^2-7.3}{17.\left(5+11\right)}=\dfrac{7.3\left(5.3-1\right)}{17.16}=\dfrac{21.14}{17.16}=\dfrac{3.7.7.2}{17.2^4}=\dfrac{3.7^2}{17.2^3}\)

a)271.11

\(a.271.11-17.11\)

\(=\left(271-17\right).11\)

\(=254.11\)

\(=2794\)

1/\(a,271\cdot11-17\cdot11=11\left(271-17\right)=11\cdot200=2200\)
\(b,136\cdot23+136\cdot17+40\cdot36=136\left(23+17\right)+40\cdot36=136\cdot40+40\cdot36=40\left(136+36\right)=40\cdot172=6880\)
2/\(a,17\cdot6^2-230:x=584\Rightarrow17\cdot36-230:x=584\Rightarrow612-230:x=584\Rightarrow230:x=612-584=28\Rightarrow x=230:28=\frac{230}{28}=\frac{115}{14}\)
\(b,293-2^3\cdot3^3+x:25=80\Rightarrow293-8\cdot27+x:25=80\Rightarrow293-216-80+x:25=0\Rightarrow x:25=3\Rightarrow x=3\cdot25=75\)

\(c,4\cdot5^2-x:2=9\Rightarrow4\cdot25-9=x:2\Rightarrow x:2=91\Rightarrow x=91\cdot2=182\)

\(=7^2+2\cdot13\cdot7+13^2=\left(7+13\right)^2=20^2=400\)

vui lòng ghi bài ra

`x*27+3*14+16*9=213`

`=>x*27+42+144=213`

`=>x*27+42=213-144`

`=>x*27+42=69`

`=>x*27=69-42`

`=>x*27=27`

`=>x=27:27`

`=>x=1`