trả lời 

\(\frac{2^{10}.13.2^{10}.65}{28.104}\)=\(\frac{2^{20}.13^2.5}{2^5.7.13}=\frac{2^{15}.13.5}{7}\)

nếu thấy đúng thì tích 

nếu sai thì thì thôi

\(2^{10}.13+2^{10}.65:2^8.104=2^{10}.78:2^8.104=2^2.78.104=4.78.104=32448\)

Bài 1 

A= \(\frac{81^{10}.3^{17}}{27^{10}.9^{13}}\)

= \(\frac{\left(3^4\right)^{10}.3^{17}}{\left(3^3\right)^{10}.\left(3^2\right)^{13}}\)

= \(\frac{3^{40}.3^{17}}{3^{30}.3^{26}}\)

= \(\frac{3^{57}}{3^{56}}\)= 3

\(\frac{x}{7}\)= \(\frac{-12}{49}\)

=> 49x = (-12) x 7 

=> 49x = -84

=> x= \(\frac{-12}{7}\)

1) \(A=\frac{3^{40}.3^{17}}{3^{30}.3^{26}}=\frac{3^{57}}{3^{56}}=3\)

2) \(\Leftrightarrow49x=-84\Rightarrow x=-\frac{12}{7}\)

k mik nha bn, tks

a,10x+65=125

   10x      =125-65

       x      =60:10

       x      =6

Vậy:...

b,45-(5-2x)^3=2.3^2

   45-(5-2x)^3=18

    (5-2x)^3    =45-18

    (5-2x)^3    =27=3^3

=> 5-2x  = 3

     2x = 5-3

     x= 2:2

     x=1

Vậy:....

-Hok tốt ~ K mk nhak.

a, 10x + 65 = 125

10x = 125 - 65

10x = 60

x = 60 : 10

x = 6

b,45-(5-2x)^3=2.3^2

45 - ( 5 - 2x )^3 =18

(5 - 2x)^3 = 45 - 18

(5 - 2x )^3= 3^3

5 - 2x = 3

2x = 2

x = 1

c,2(x-3)-12=(-10)

2x - 6 -12 =-10

2x = -10 + 6 + 12

2x = 8

x = 4

d,x-12=(-13)+1+|-13|

x - 12 = -13 + 1 + 13

x - 12 = 1

x = 13

hok tốt!!!

\(\text{a)}\)\(10x+65=125\)

\(\Rightarrow10x=60\)

\(\Rightarrow x=6\)

\(b\text{)}\)\(45-\left(5-2x\right)^3=2.3^2\)

\(\Rightarrow45-\left(5-2x\right)^3=18\)

\(\Rightarrow\left(5-2x\right)^3=45-18\)

\(\Rightarrow\left(5-2x\right)^3=27\)

\(\Rightarrow\left(5-2x\right)^3=3^3\)

\(\Rightarrow5-2x=3\)

\(\Rightarrow2x=2\Rightarrow x=1\)

\(A=\frac{2^{10}.13+2^{10}.65}{2^8.104}=\frac{2^{10}.\left(13+65\right)}{2^8.104}=\frac{2^{10}.78}{2^8.104}=3\)

\(A=\frac{2^{10}.13+2^{10}.65}{2^8.104}=\frac{2^{10}\left(13+65\right)}{2^8.104}=\frac{2^{10}.78}{2^8.104}=\frac{2^2.78}{104}=\frac{2^2.2.39}{2^3.13}=\frac{2^3.39}{2^3.13}=3\)

\(A=\frac{2^{10}.13+2^{10}.65}{2^8.104}\)

\(=>A=\frac{2^{10}.\left(65+35\right)}{2^8.104}=\frac{2^{10}.78}{2^8.104}=3\)