a: =>1/3:x=3/5-2/3=9/15-10/15=-1/15

=>x=-1/3:1/15=5

b: \(\Leftrightarrow x\cdot\dfrac{2}{3}-3=\dfrac{2}{5}\cdot\left(-10\right)=-4\)

=>x*2/3=-1

=>x=-3/2

c: =>2x+1=4 hoặc 2x+1=-4

=>x=3/2 hoặc x=-5/2

h: =>x-3=4

=>x=7

g: =>2x-1=3

=>2x=4

=>x=2

f: \(\Leftrightarrow x\cdot\left(\dfrac{3}{2}-\dfrac{7}{3}\right)=\dfrac{3}{2}-\dfrac{2}{3}\)

=>x*-5/6=5/6

=>x=-1

d: =>|2x-1|=3

=>2x-1=3 hoặc 2x-1=-3

=>x=-1 hoặc x=2

\(\left(2x-\dfrac{3}{2}\right)^2=\dfrac{49}{81}\\ \Rightarrow\left(2x-\dfrac{3}{2}\right)^2=\left(\dfrac{7}{9}\right)^2\\ \Rightarrow2x-\dfrac{3}{2}=\pm\dfrac{7}{9}\\ \Rightarrow\left[{}\begin{matrix}2x-\dfrac{3}{2}=\dfrac{7}{9}\\2x-\dfrac{3}{2}=-\dfrac{7}{9}\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}2x=\dfrac{41}{18}\\2x=\dfrac{13}{18}\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{41}{36}\\x=\dfrac{13}{36}\end{matrix}\right.\)

(2x-3/2)²=49/81=(7/9)²

=>2x-3/2=7/9 hoặc 2x-3/2=-7/9

=>x=41/36 hoặc x=13/36.

\(\left(2x-\dfrac{3}{2}\right)^2=\dfrac{49}{81}=\left(\dfrac{7}{9}\right)^2=\left(-\dfrac{7}{9}\right)^2\\ \Rightarrow\left[{}\begin{matrix}2x-\dfrac{3}{2}=\dfrac{7}{9}\\2x-\dfrac{3}{2}=-\dfrac{7}{9}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=\dfrac{7}{9}+\dfrac{3}{2}=\dfrac{41}{18}\\2x=-\dfrac{7}{9}+\dfrac{3}{2}=\dfrac{13}{18}\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{41}{18}:2=\dfrac{41}{36}\\x=\dfrac{13}{18}:2=\dfrac{13}{36}\end{matrix}\right.\)

\(3^{2x}=81^2\)

\(3^{2x}=(3^4)\)

\(3^{2x}=3^8\)

\(2x=8\)

\(x=8\div2\)

\(x=4\)

ồ tôi thấy nó ko giống toán 6

toán 7 đko?

a)5^x=125

125=5^3

5^x=5^3

=>x=3

b)3^2x=81

81=3^4

3^2x=3^4

=>2x=4

x=4:2

x=2

3

Bài lớp mấy vậy ?

Ai trả lời nhanh mik k cho

Có trl ko

\(4.\left(3-2x\right)^2=\frac{1}{81}\)

\(\left(3-2x\right)^2=\frac{1}{324}\)

\(\Leftrightarrow\orbr{\begin{cases}3-2x=\frac{1}{18}\\3-2x=\frac{-1}{18}\end{cases}\Leftrightarrow\orbr{\begin{cases}x=\frac{53}{36}\\x=\frac{55}{36}\end{cases}}}\)

Vậy \(x\in\left\{\frac{53}{36};\frac{55}{36}\right\}\)

Cảm ơn nhé!

zko có gì

a) 3^2x=9^2

3^2x=3^2.3^2

3^2x=3^4

3^2x=3^2.2

=>2x=2.2

=>x=4/2

=>x=2

a, 2^x-1 = 64

=> 2^x-1 = 2⁶

=> x - 1 = 6

=> x = 6 + 1 

=> x = 7

b, 3^2x-10 = 81

=> 3^2x-10 = 3⁴

=> 2x - 10 = 4

=> 2x = 14

=> x = 7

c, 2^2x+3 = 1024

=> 2^2x+3 = 2¹⁰

=> 2x + 3 = 10

=> 2x = 7

=> x = \(\frac{7}{2}\)