5^x.5^6=5^3

5^x.(5³)²=625

=> 5^x.5⁶=5⁴

=> 5^x=5⁴:5⁶

=> 5^x=5^-2

=> x=-2

Vậy x=-2

\(^{=>5^x.5^6=5^4}\)

=> \(5^x=5^{4-6}\)

=>x=-2

Sai đề nha bạn

5^x.5^6=5^4

5^x=5^4:5^6

5^x= tap hop rong

Suy ra x= tap hop rong

\(5^x.\left(5^3\right)^2=625\)

\(5^x.5^6=5^4\)

\(5^x=5^4\text{ }:\text{ }5^6\)

\(5^x=5^{-2}\)

\(\Rightarrow\text{ }x=-2\)

5^x . ( 5³ )² = 625

<=> 5^x . 5⁶ = 625

<=> 5^x+6 = 625

<=> 5^x+6 = 5⁴

<=> x + 6 = 4

<=> x = -2

\(5^x.\left(5^3\right)^2=625\)

\(\Leftrightarrow5^x.5^6=625\)

\(\Leftrightarrow5^x=\frac{1}{5^2}\)

\(\Leftrightarrow x=-2\)

      \(5^x\times\left(5^3\right)^2=625\)

\(\Rightarrow5^x\times5^6=625\)

      \(5^{x+6}=5^4\)

 \(\Rightarrow x+6=4\)

      \(x=-2\)

    Vậy x = -2

(7.x + 1) : 2 - 23 = 2

=> (7.x + 1) : 2 = 2 + 23

=> (7.x + 1) : 2 = 25

=> 7.x + 1 = 25 . 2

=> 7.x + 1 = 50

=> 7.x = 50 - 1

=> 7.x = 49

=> x = 49 : 7 = 7

(7.x + 1) : 2 - 23 = 2

=> (7.x + 1) : 2 = 2 + 23

=> 7.x + 1 = 25 . 2

=> 7.x = 50 - 1

=> 7.x = 49

 x = 49 : 7 = 7

Vậy.............

hok tốt

Ta có: 25^{x + 1} . 125^x . 625^{x + 2} = (5²)⁵

=> (5²)^{x + 1} . (5³)^x  . (5⁴)^{x+ 1} = 5¹⁰

=> 5^{2x + 2} . 5^3x . 5^{4x + 8} = 5¹⁰

=> 2x + 2 + 3x + 4x + 8 = 10

=> 9x + 2 + 8 = 10

=> 9x = 10 - 2 - 8

=> 9x = 0

=> x = 0 : 9

=> x = 0

5^{x .} 5^x+1= 625

5^x+x+1= 625

5^x+x+1=5⁴

=>x+x+1=4

2x+1=4

2x=4-1

2x=3

x=3:2

x=1,5

5^x.15625=625
56^x=625:15625
56^x=0,04
x=-2
b)-13/35

x^5=625.x 

<=>x^5:x=625

<=>x^4=625

<=>x^4=5^4

<=>x=5