a) \(\dfrac{3}{5}:x=3\)

\(x=\dfrac{3}{5}:3\)

\(x=\dfrac{3}{5}\times\dfrac{1}{3}\)

\(x=\dfrac{1}{5}\)

b) \(\dfrac{x}{5}:\dfrac{3}{8}=\dfrac{8}{5}\)

\(\dfrac{x}{5}=\dfrac{8}{5}\times\dfrac{3}{8}\)

\(\dfrac{x}{5}=\dfrac{3}{5}\)

\(=>x=3\)

a,x=3/5:3/

x=3/5.1/3

x=1/5

b,x/5=8/5.3/8

x/5=3/5

=> x=3

`a)3/5:x=3`

`x=3/5:3=3/5xx1/3`

`x=1/5`

`b)x/5:3/8=8/5`

`x/5=8/5xx3/8`

`x/5=3/5`

`x=3`

\(a,\left(x+2\right)^{10}+\left(x+2\right)^8=0\\ \Leftrightarrow\left(x+2\right)^8\left[\left(x+2\right)^2+1\right]=0\\ \Leftrightarrow\left[{}\begin{matrix}\left(x+2\right)^8=0\\\left(x+2\right)^2+1=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x+2=0\\\left(x+2\right)^2=-1\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-2\\x\in\varnothing\end{matrix}\right.\\ b,\left(x+3\right)^{10}-\left(x+3\right)^8=0\\ \Leftrightarrow\left(x+3\right)^8\left[\left(x+3\right)^2-1\right]=0\\ \Leftrightarrow\left[{}\begin{matrix}\left(x+3\right)^8=0\\\left(x+3\right)^2-1=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x+3=0\\\left(x+3\right)^2=1\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-3\\x+3=1\\x+3=-1\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-3\\x=-2\\x=-4\end{matrix}\right.\)

a) => x - 8 = 0 hoặc x³ + 8 = 0

+) x - 8 = 0 => x = 8

+) x³ + 8 = 0 => x³ = - 8 = (-2)³ => x = -2

Vậy x = 8; -2

b) => 4x - 3 - x - 5 = 30 - 3x

=> 3x - 8 = 30 - 3x

=> 3x + 3x = 30 + 8

=> 6x = 38 => x = 38/6 = 19/3

Vậy x = 19/3

a) => x - 8 = 0 hoặc x³ + 8 = 0

+) x - 8 = 0 => x = 8

+) x³ + 8 = 0 => x³ = - 8 = (-2)³ => x = -2

Vậy x = 8; -2

b) => 4x - 3 - x - 5 = 30 - 3x

=> 3x - 8 = 30 - 3x

=> 3x + 3x = 30 + 8

=> 6x = 38 => x = 38/6 = 19/3

Vậy x = 19/3

a)(x-8)(x³+8)=0

<=>x-8=0 hoặc x³+8=0

<=>x=8 hoặc x³=-8

<=>x=8 hoặc x=-2

b)(4x-3)-(x+5)=3(10-x)

<=>4x-3-x-5=30-3x

<=>(4x-x)+(-3-5)=30-3x

<=>3x-8=30-3x

<=>6x=38

<=>x=\(\frac{38}{6}=\frac{19}{3}\)

a)

x³ + 8 = 0                                     x - 8 = 0

x³        = -8                                     x      = 8

x        =-2

a) (x-8)(x^3+8)=0

=>x-8=0 hoặc x^3+8=0

x-8=0               x^3+8=0             

x   =0+8           x^3=0-8

x   =0               x^3=-8

                        x^3=-2^3

                        x=-2

=>x=8 hoặc x= -2

a)(x-8)*(x^3+8)=0

nên x-8=0 hoặc x^3+8=0

       x=0+8          x^3=0-8

       x=8       hoặc x^3=-8

                              x=-2

vậy x=8 hoặc x=-2

b)(4x-3)-(x+5)=3(10-x)

     4x-3-x-5=30-3x(quy tắc bỏ ngoặc)

    3x-8=30-3x

          3x+3x=30+8(chuyển vế)

           6x=38

             x=38:6

x=19/3

a) x + 43657 = 72024

x = 72024 - 43657 = 28367

b) x + 1/4 = 7/8 - 3/8 = 1/2

x = 1/2 - 1/4 = 1/4

a, x=28367
b, x=1/4

a) x + 43657 = 72024

    x = 72024 - 43657

    x = 28367

b) x + 1/4 = 7/8 - 3/8

    x + 1/4 = 4/8

    x =  4/8 - 1/4

    x = 1/4 

chúc bn học tốt!

a)  x = 200   

b) x = 450

c)  x = 21

d)  x = 9 hoặc x = 36

Vế trái=5/3 x 8/a x 3/5 =(5/3x3/5)x 8/a= 1x 8/a= 8/a

Vế phải= 8/15

VT=VT

<=> 8/a= 8/15

=> a=15

5/3 x 8/a x 3/5 = 8/15

<=> 8/a=8/15

=> a=15

=8/15 học tốt