K
Khách

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

25 tháng 2 2020

2(x+3/5)=5-(13/5+x)

<=>2x+6/5=5-13/5-x

<=>2x+6/5-5+13/5+x=0

<=>3x-6/5=0

<=>3x=6/5

<=>x=2/3

Vậy phương trình có nghiệm duy nhất x=2/3

25 tháng 2 2020

\(2\left(x+\frac{3}{5}\right)=5-\left(\frac{13}{5}+x\right)\)

\(\Leftrightarrow2x+\frac{6}{5}=5-\frac{13}{5}-x\)

\(\Leftrightarrow2x+\frac{6}{5}=\frac{12}{5}-x\)

\(\Leftrightarrow2x+\frac{6}{5}-\frac{12}{5}+x=0\)

\(\Leftrightarrow3x-\frac{6}{5}=0\)

\(\Leftrightarrow3x=\frac{6}{5}\)

\(\Leftrightarrow x=\frac{6}{15}=\frac{2}{5}\)

25 tháng 2 2020

\(2\left(x+\frac{3}{5}\right)=5-\left(\frac{13}{5}+x\right)\\\Leftrightarrow 2\left(\frac{5x}{5}+\frac{3}{5}\right)=\frac{25}{5}-\left(\frac{13}{5}+\frac{5x}{5}\right)\\ \Leftrightarrow\frac{2\left(5x+3\right)}{5}=\frac{12-5x}{5}\\\Leftrightarrow 2\left(5x+3\right)=12-5x\\ \Leftrightarrow10x+6=12-5x\\ \Leftrightarrow10x+5x=-6+12\\\Leftrightarrow 15x=6\\ \Leftrightarrow x=\frac{2}{5}\)

Vậy phương trình trên có nghiệm là \(\frac{2}{5}\)

11 tháng 8 2021

1/ \(7x-5=13-5x\)

\(\Leftrightarrow12x=18\)

\(\Leftrightarrow x=\dfrac{3}{2}\)

Vậy: \(S=\left\{\dfrac{3}{2}\right\}\)

==========

2/ \(19+3x=5-18x\)

\(\Leftrightarrow21x=-14\)

\(\Leftrightarrow x=-\dfrac{2}{3}\)

Vậy: \(S=\left\{-\dfrac{2}{3}\right\}\)

==========

3/ \(x^2+2x-4=-12+3x+x^2\)

\(\Leftrightarrow-x=-8\)

\(\Leftrightarrow x=8\)

Vậy: \(S=\left\{8\right\}\)

===========

4/ \(-\left(x+5\right)=3\left(x-5\right)\)

\(\Leftrightarrow-x-5=3x-15\)

\(\Leftrightarrow-4x=-10\)

\(\Leftrightarrow x=\dfrac{5}{2}\)

Vậy: \(S=\left\{\dfrac{5}{2}\right\}\)

==========

5/ \(3\left(x+4\right)=\left(-x+4\right)\)

\(\Leftrightarrow3x+12=-x+4\)

\(\Leftrightarrow4x=-8\)

\(\Leftrightarrow x=-2\)

Vậy: \(S=\left\{-2\right\}\)

[----------]

11 tháng 8 2021

1. \(7x-5=13-5x\) \(\Leftrightarrow12x=18\Leftrightarrow x=\dfrac{3}{2}\)

2. \(19+3x=5-18x\Leftrightarrow21x=-14\Leftrightarrow x=-\dfrac{2}{3}\)

3. \(x^2+2x-4=-12+3x+x^2\Leftrightarrow-x=-8\Leftrightarrow x=8\)

4. \(-\left(x+5\right)=3\left(x-5\right)\Leftrightarrow-x-5=3x-15\Leftrightarrow4x=10\Leftrightarrow x=\dfrac{5}{2}\)

5. \(3\left(x+4\right)=-x+4\Leftrightarrow3x+12=-x+4\Leftrightarrow4x=-8\Leftrightarrow x=-2\)

 

8 tháng 1 2019

2.(\(\dfrac{x+3}{5}\)) = 5 - (\(\dfrac{13}{5}\) + x)

MSC = 5

2(\(\dfrac{x+3}{5}\)) = 5 - (\(\dfrac{13}{5}\)+x)

\(\Rightarrow\)\(\dfrac{2\left(x+3\right)}{5}\) = 5 - \(\dfrac{13+5x}{5}\)

\(\Rightarrow\) 2x + 6 = 5 - 13 - 5x

\(\Rightarrow\) 2x + 5x = 5 -13 -6

\(\Rightarrow\) 7x = -14

\(\Rightarrow\) x = -2

Vậy S =\(\left\{-2\right\}\)

10 tháng 8 2020

a, \(3x-5=13\Leftrightarrow3x=18\Leftrightarrow x=6\)

b, \(4x-2=3x+1\Leftrightarrow x=3\)

c, \(5\left(x-3\right)-2\left(x-5\right)=58\Leftrightarrow5x-15-2x+10=58\)

\(\Leftrightarrow3x-5=58\Leftrightarrow3x=63\Leftrightarrow x=21\)

d, \(mx+5x=m^2m^2-25\Leftrightarrow x\left(m+5\right)=m^4-25\)

10 tháng 8 2020

mk quên phần cuối nhé 

\(\Leftrightarrow x\left(m+5\right)=m^4-25\Leftrightarrow x=\frac{m^4-25}{m+5}\)

7 tháng 2 2022

A 3x-4x=-9-3

    -x=-12

     x=12

B 3.2x -5x +1=5+0.2x

  3.2x-5x-0.2x=5-1

  -2x=4

 x=-2

C 1.5-x-2=-3x-0.3

  -x+3x=-0.3-1.5+2

  2x =0.2

  x=0.1

E 2/3-1/2x-1=-x+1

  -1/2x+x=1+1-2/3

  1/2x=4/3

  x=8/3

F 3t-4+13+2t+4-3t

  =3t+2t-3t-4+13+4

  =2t+13

7 tháng 8 2018

a) \(\dfrac{10^{12}+5^{11}.2^9-5^{13}.2^8}{4.5^5.10^6}\)

\(=\dfrac{2^{12}.5^{12}+5^{11}.2^9-5^{13}.2^8}{2^2.5^5.2^6.5^6}\)

\(=\dfrac{2^{12}.5^{12}+5^{11}.2^9-5^{13}.2^8}{2^8.5^{11}}\)

\(=\dfrac{\left(2^8.5^{11}\right)\left(2^4.5+2-5^2\right)}{2^8.5^{11}}\)

\(=2^4.5+2-5^2\)

\(=57\)

b) \(\dfrac{\left[5\left(x-y\right)^4-3\left(x-y\right)^3+4\left(x-y\right)^2\right]}{\left(y-x\right)^2}\)

\(=\dfrac{\left(x-y\right)^2\left[5\left(x-y\right)^2-3\left(x-y\right)+4\right]}{\left(y-x\right)^2}\)

\(=\dfrac{\left(x^2+y^2-2xy\right)\left[5\left(x-y\right)^2-3\left(x-y\right)+4\right]}{\left(y^2+x^2-2xy\right)}\)

\(=5\left(x-y\right)^2-3\left(x-y\right)+4\)

c) \(\dfrac{\left(x+y\right)^5-2\left(x+y\right)^4+3\left(x+y\right)^3}{-5\left(x+y\right)^3}\)

\(=\dfrac{\left(x+y\right)^3\left[5\left(x+y\right)^2-2\left(x+y\right)+3\right]}{-5\left(x+y\right)^3}\)

\(=\dfrac{5\left(x+y\right)^2-2\left(x+y\right)+3}{-5}\)

9 tháng 8 2020

Bài 2 Tìm x biết

a) 3x -5 = 13

<=> 3x = 18

<=> x = 6

Vậy x = 6

b) 4x - 2 = 3x + 1

<=> 4x - 3x = 2 + 1

<=> x = 3

Vậy x = 3

c) 5(x - 3) - 2(x - 5) = 58

<=> 5x - 15 - 2x + 10 = 58

<=> 3x - 5 = 58

<=> 3x = 63

<=> x = 21

Vậy x = 21

d) mx + 5x = m2 - 25

<=> mx + 5x + 25 - m2 = 0

<=> x(5 + m) + (5 - m)(5 + m) = 0

<=> (5 + m)(x + 5 - m) = 0

<=> \(\left[{}\begin{matrix}5+m=0\\x+5-m=0\end{matrix}\right.\) <=>\(\left[{}\begin{matrix}m=-5\\x+5-m=0\end{matrix}\right.\) => x + 5 - (-5) = 0

<=> x + 10 = 0

<=> x = -10

Vậy x = -10

#Không chắc lắm :)