\(a,3.5^{x+1}-100=-25\\ 3.5^{x+1}=-25+100\\ 3.5^{x+1}=75\\ 5^{x+1}=75:3\\ 5^{x+1}=25\\ 2^{x+1}=5^2\\ x+1=2\\ x=2-1\\ x=1\)

\(b,4x-26+2x=28\\ 4x+2x-26\\ 6x-26=28\\ 6x=28+26\\ 6x=54\\ x=54:6\\ x=9\)

viết latex đi bn ơi!

a,x=6² ...6⁸

b: Ta có: \(100< 5^{2x-1}< 5^6\)

\(\Leftrightarrow2x-1\in\left\{3;5\right\}\)

hay \(x\in\left\{2;3\right\}\)

2:

a: 2,75<x<4,05

mà x là số tự nhiên

nên x=3 hoặc x=4

b: 10,478<x<11,006

mà x là số tự nhiên

nên x=11

a) 29 + 2x = 59

            2x = 59 - 29

            2x = 30

              x = 30 : 2

              x = 15

b) 2020 - 6(17-x) = 2002

               6(17-x) = 2020 - 2002

              6(17-x) = 18

                 17-x = 18 : 6

                 17-x = 3

                      x = 17 - 3

                      x = 14

\(a,\text{Vì }x,y\in N\Leftrightarrow x+2\ge2;y+3\ge3\\ \Leftrightarrow\left(x+2\right)\left(y+3\right)=6=2\cdot3=3\cdot2\\ \Leftrightarrow\left\{{}\begin{matrix}x+2=2\\y+3=3\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=0\\y=0\end{matrix}\right.\)

Vậy \(\left(x;y\right)=\left(0;0\right)\)

\(b,\Leftrightarrow\left(x-3\right)\left(y+1\right)=7\cdot1=1\cdot7\\ \left\{{}\begin{matrix}x-3=7\\y+1=1\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=10\\y=0\end{matrix}\right.\\ \left\{{}\begin{matrix}x-3=1\\y+1=7\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=4\\y=6\end{matrix}\right.\)

Vậy \(\left(x;y\right)\in\left\{\left(10;0\right);\left(4;6\right)\right\}\)

a) x=3 y=13

x=16 y=0

x=4 y=5

x=9 y=1

a) \(\left(x-2\right)\left(y+1\right)=14\)

Do \(x,y\in N\)

\(\Rightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x-2=1\\y+1=14\end{matrix}\right.\\\left\{{}\begin{matrix}x-2=14\\y+1=1\end{matrix}\right.\\\left\{{}\begin{matrix}x-2=2\\y+1=7\end{matrix}\right.\\\left\{{}\begin{matrix}x-2=7\\y+1=2\end{matrix}\right.\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x=3\left(tm\right)\\y=13\left(tm\right)\end{matrix}\right.\\\left\{{}\begin{matrix}x=16\left(tm\right)\\y=0\left(tm\right)\end{matrix}\right.\\\left\{{}\begin{matrix}x=4\left(tm\right)\\y=6\left(tm\right)\end{matrix}\right.\\\left\{{}\begin{matrix}x=9\left(tm\right)\\y=1\left(tm\right)\end{matrix}\right.\end{matrix}\right.\)

`2x-15 = 17``

`=> 2x  = 17 + 15`

`=>  2x = 32`

`=>    X = 32 : 2`

`=>    x = 16`

`156 - (x + 61) = 82`

`=>      x + 61  = 156 - 82`

`=>      x + 61   = 74`

`=>       x           = 13`

`2x - 138 = 2^3 . 3^2`

`=>2x - 138 = 72`

`=>  2x        = 210`

`=>   x         = 105`

bài 2:

`23-3x = 8`

`=>  3x = 23 - 8`

`=>   3x = 15`

`=>     x  = 5`

`(x-35) - 120 = 0`

`=>(x-35)      = 120`

`=> x            = 120  +35`

`=>  x           = 155`

`3^x + 2 = 29`

`=>  3^x = 27`

`=>  3^x = 3^3`

`=> x      = 3` 

a: \(x+1\in\left\{1;11\right\}\)

hay \(x\in\left\{0;10\right\}\)

b: \(\Leftrightarrow x+1\in\left\{1;7\right\}\)

hay \(x\in\left\{0;6\right\}\)