\(27.3^x=3^{12}:3^3\\ =>27.3^x=3^9\\ =>3^3.3^x=3^9\\ =>3^{3+x}=3^9\\ =>x+3=9\\ =>x=6\\ \)

27 . 3^x = 3¹² : 3³

 27 . 3^x = 3⁹

3³ . 3^x = 3⁹ 

 3^x =  3⁹ : 3³ 

 3^x =  3⁶ 

x = 6

150 nha 

\(\left(x-3\right)\left(4x-16\right)=0\\ =>\left[{}\begin{matrix}x-3=0\\4x-16=0\end{matrix}\right.=>\left[{}\begin{matrix}x=3\\4x=16\end{matrix}\right.=>\left[{}\begin{matrix}x=3\\x=4\end{matrix}\right.\)

    (x - 3).(4x - 16) = 0

⇒ \(\left[{}\begin{matrix}x-3=0\\4x-16=0\end{matrix}\right.\)

⇒ \(\left[{}\begin{matrix}x=3\\4x=16\end{matrix}\right.\)

⇒ \(\left[{}\begin{matrix}x=3\\x=16:4\end{matrix}\right.\)

⇒ \(\left\{{}\begin{matrix}x=3\\x=4\end{matrix}\right.\)

                 vậy x = 3 hoặc x = 4

\(a,A=\left\{10;15;20;25;30;35;40;45;50;55;60;65;70;75;80;85;90;95\right\}\)

\(b,B=\left\{10;20;30;40;50;60;70;80;90\right\}\)

a) A={10;15;20;...;90;95}

b) B={10;20;...;90}

`2x^2+4=3x^2`

`x^2=4`

`x=2` hoặc `x=-2`

       2X² + 4 = 3X²

⇒ 3X² - 2X² = 4

⇒            X² = 4

⇒            X² = 2² = (-2)²

⇒            X = 2; -2

\(23+5^2-\left\{11-\left[3^2-2.\left(5^2-3.2^3\right)\right]\right\}\\ =23+25-\left\{11-\left[9-2.\left(25-24\right)\right]\right\}\\ =48-\left[11-\left(9-2.1\right)\right]\\ =48-\left(11-7\right)\\ =48-4\\ =44\)

5^x + 5^{x + 2} = 650 

<=> 5^x + 5^x.25 = 650 

<=> 5^x . 26 = 650

<=> 5^x = 25 

<=> 5^x = 5² 

<=>  x = 2

32 ⋮ x hay x ϵ B ( 32 ) 

B ( 32 ) = { 1 ; 2 ; 4 ; 8 . 16 . 32 }

28 ⋮ x hay x ϵ B ( 28 )

B ( 28 ) = { 1 ; 2 ; 4 ; 7 ; 14 ; 28 }

Vì 1 < x < 7 nên x ϵ { 1 ; 2 ; 4 }

4 và 2 thế thui