K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

28 tháng 3 2020

a,

(x-2)^3=-27

<=>(x-2)^3=-3^3

<=>x-2=-3

<=>x=-1

vậy .....

b,

3(x+2)^4=48

<=>(x+2)^4=16

<=>(x+2)^4=2^4=(-2)^4

<=>\(\orbr{\begin{cases}x+2=2\\x+2=-2\end{cases}< =>\orbr{\begin{cases}x=0\\x=-4\end{cases}}}\)

vậy ..........

28 tháng 3 2020

a ) Ta có : \(\left(x-2\right)^3=-27\)

\(\Rightarrow\left(x-2\right)^3=\left(-3\right)^3\)

\(\Rightarrow x-2=-3\)

\(\Rightarrow x=-3+2\)

\(\Rightarrow x=-1\)

Vậy \(x=-1\)

b) Ta có : \(3.\left(x+2\right)^4=48\)

\(\Rightarrow\left(x+2\right)^4=16\)

\(\Rightarrow\orbr{\begin{cases}\left(x+2\right)^4=2^4\\\left(x+2\right)^4=\left(-2\right)^4\end{cases}}\) 

\(\Rightarrow\orbr{\begin{cases}x+2=2\\x+2=-2\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}x=0\\x=-4\end{cases}}\)

Vậy \(x=0;x=-4\) 

a: x/2=-5/y

=>xy=-10

=>\(\left(x,y\right)\in\left\{\left(1;-10\right);\left(-10;1\right);\left(-1;10\right);\left(10;-1\right);\left(2;-5\right);\left(-5;2\right);\left(-2;5\right);\left(5;-2\right)\right\}\)

b: =>xy=12

mà x>y>0

nên \(\left(x,y\right)\in\left\{\left(12;1\right);\left(6;2\right);\left(4;3\right)\right\}\)

c: =>(x-1)(y+1)=3

=>\(\left(x-1;y+1\right)\in\left\{\left(1;3\right);\left(3;1\right);\left(-1;-3\right);\left(-3;-1\right)\right\}\)

=>\(\left(x,y\right)\in\left\{\left(2;2\right);\left(4;0\right);\left(0;-4\right);\left(-2;-2\right)\right\}\)

d: =>y(x+2)=5

=>\(\left(x+2;y\right)\in\left\{\left(1;5\right);\left(5;1\right);\left(-1;-5\right);\left(-5;-1\right)\right\}\)

=>\(\left(x,y\right)\in\left\{\left(-1;5\right);\left(3;1\right);\left(-3;-5\right);\left(-7;-1\right)\right\}\)

Tham khảo:Tìm x thuộc N , biết:a)  2x + 2x+3  =144b) (4x -1)2 =25 x 9  - Hoc24

7 tháng 8 2021

câu a khác bạn ơi

`@` ` \text {Ans}`

`\downarrow`

`a,`

`1/4+3/4*x=3/2-x`

`=> 1/4 + 3/4x - 3/2 + x = 0`

`=> (1/4 - 3/2) + (3/4x + x) = 0`

`=> -5/4 + 7/4x = 0`

`=> 7/4x = 5/4`

`=> x = 5/4 \div 7/4`

`=> x = 5/7`

Vậy, `x=5/7`

`b,`

`3/5*x-1/4=1/10*x-1/2`

`=> 3/5x - 1/4 - 1/10x + 1/2 = 0`

`=> (3/5x - 1/10x) + (-1/4 + 1/2)=0`

`=> 1/2x + 1/4 = 0`

`=> 1/2x = -1/4`

`=> x = -1/4 \div 1/2`

`=> x = -1/2`

Vậy, `x=-1/2`

`c,`

`3x-3/5=x-1/4`

`=> 3x - 3/5 - x + 1/4 = 0`

`=> (3x - x) - (3/5 - 1/4) = 0`

`=> 2x - 7/20 = 0`

`=> 2x = 0,35`

`=> x = 0,35 \div 2`

`=> x = 7/40`

Vậy, `x=7/40`

`d,`

`3/2*x-2/5=1/3*x-1/4`

`=>  3/2x - 2/5 - 1/3x + 1/4 = 0`

`=> (3/2x - 1/3x) - (2/5 - 1/4) = 0`

`=> 7/6x - 3/20 = 0`

`=> 7/6x = 3/20`

`=> x = 3/20 \div 7/6`

`=> x = 9/70`

Vậy, `x=9/70`

`@` `\text {Kaizuu lv uuu}`

18 tháng 1 2022

\(a,2x-5+17=6\\ \Rightarrow2x=-6\\ \Rightarrow x=-3\\ b,\Leftrightarrow10-8+6x=-4\\ \Leftrightarrow6x=-6\Leftrightarrow x=-1\\ d,\Rightarrow-2x=-10\\ \Rightarrow x=5\)

câu c giống câu b nhó

14 tháng 3 2023

`a) 14,58 - x= -3,72`

`=> x= 14,58 - ( -3,72)`

`=> x= 14,58+ 3,72`

`=>x=18,3`

`b)3/4 + 1/2.x= -5/6`

`=>  1/2.x= -5/6-3/4`

`=>  1/2.x= -19/12``=>x=-19/12 : 1/2``=>x=-19/12xx2``=>x= -19/6`
14 tháng 3 2023

\(a)14,58-x=-3,72\\ x=14,58-\left(-3,72\right)\\ x=14,58+3,72\\ x=18,3\\ b)\dfrac{3}{4}+\dfrac{1}{2}.x=-\dfrac{5}{6}\\ \dfrac{1}{2}.x=-\dfrac{5}{6}-\dfrac{3}{4}\\ \dfrac{1}{2}.x=-\dfrac{19}{12}\\ x=-\dfrac{19}{12}:\dfrac{1}{2}\\ x=-\dfrac{19}{6}.\)

2 tháng 5 2021

a, \(\left(\dfrac{1}{2}+\dfrac{4}{7}\right):x=\dfrac{-3}{4}\)

\(\dfrac{15}{14}:x=\dfrac{-3}{4}\)

=> x= \(\dfrac{-7}{10}\)

b, 0,5:x-\(1\dfrac{3}{4}\)= 25%

0,5:x-\(\dfrac{7}{4}=\dfrac{1}{4}\)

0,5:x = 2

=> x = \(\dfrac{1}{4}\)

a: =>3x+3=5x-25

=>-2x=-28

hay x=14

b: =>3x+6=-4x+20

=>7x=14

hay x=2

12 tháng 3 2022

undefined

a: \(\left(\dfrac{3}{4}x+2\dfrac{1}{2}\right)\cdot\dfrac{-2}{3}=\dfrac{1}{8}\)

=>\(\left(\dfrac{3}{4}x+\dfrac{5}{2}\right)=\dfrac{1}{8}:\dfrac{-2}{3}=\dfrac{-3}{16}\)

=>\(\dfrac{3}{4}x=-\dfrac{3}{16}-\dfrac{5}{2}=-\dfrac{3}{16}-\dfrac{40}{16}=-\dfrac{43}{16}\)

=>\(x=-\dfrac{43}{16}:\dfrac{3}{4}=\dfrac{-43}{16}\cdot\dfrac{4}{3}=\dfrac{-43}{12}\)

b: \(\dfrac{1}{3}\cdot x-0,5x=0,75\)

=>\(x\left(\dfrac{1}{3}-\dfrac{1}{2}\right)=0,75\)

=>\(x\cdot\dfrac{-1}{6}=0,75\)

=>\(x=-0,75\cdot6=-4,5\)