/ / là giá trị tuyệt đối hả bạn

giá trị tuyệt đối đó bạn

a) 5(2x -1) - 4(8 - 3x) = 7

<=> 10x - 5 - 32 + 12x = 7

<=> 22x = 44 

<=> x =2

Vậy x = 2 là nghiệm phương trình

b) 7(2x - 5) - 5(7x - 2) + 2(5x - 7) = (x - 2) - (x + 4) 

<=> 14x - 35 - 35x + 10 + 10x - 14 = x - 2 - x - 4

<=> -11x - 39 = - 6

<=> -11x = 33

<=> x = -3

Vậy x = -3 là nghiệm phương trình 

\(a,10x-5-32+12x=7\)

\(22x=44\)

\(x=2\)

\(b,14x-35-35x+10+10x-14=x-2-x-4\)

\(-11x-39=-6\)

\(-11x=-33\)

\(x=3\)

sửa lại đoạn cuối

\(-11x=33\)

\(x=-3\)

Ta có : |2x - 1| + 1 = x 

=> |2x - 1| = x - 1

\(\Leftrightarrow\orbr{\begin{cases}2x-1=x-1\\2x-1=1-x\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}2x-x=-1+1\\2x+x=1+1\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=0\\3x=2\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=0\\x=\frac{2}{3}\end{cases}}\)

a: \(x\in\left\{0;25\right\}\)

c: \(x\in\left\{0;5\right\}\)

k mk đi

ai k mk 

mk k lại

thanks

không ai trả lời 

a,\(2\left(3x-1\right)-5\left(x-3\right)-9\left(2x-4\right)=24\)

\(< =>6x-2-5x+15-18x+36=24\)

\(< =>-29x+49=24< =>29x=25< =>x=\frac{25}{29}\)

b,\(2x^2+4\left(x^2-1\right)=2x\left(3x+1\right)\)

\(< =>2x^2+4x^2-4=6x^2+2x\)

\(< =>2x=-4< =>x=-\frac{4}{2}=-2\)

c, \(2x\left(5-3x\right)+2x\left(3x-5\right)-3\left(x-7\right)=4\)

\(< =>10x-6x^2+6x^2-10x-3x+21=4\)

\(< =>-3x=4-21=-17< =>x=\frac{17}{3}\)

d, \(5x\left(x+1\right)-4x\left(x+2\right)=1-x\)

\(< =>5x^2+5x-4x^2-8x=1-x\)

\(< =>x^2-3x+x-1=0\)

\(< =>x^2-2x-1=0\)

\(< =>\left(x-1\right)^2=2\)

\(< =>\orbr{\begin{cases}x-1=\sqrt{2}\\x-1=-\sqrt{2}\end{cases}}\)

\(< =>\orbr{\begin{cases}x=1+\sqrt{2}\\x=1-\sqrt{2}\end{cases}}\)

Sai rồi bn:)

a, \(2\left(3x-1\right)-5\left(x-3\right)-9\left(2x-4\right)=24\)

\(\Leftrightarrow6x-2-5x+15-18x+36=24\)

\(\Leftrightarrow-17x+25=0\Leftrightarrow x=\frac{25}{17}\)

b, \(2x^2+4\left(x^2-1\right)=2x\left(3x+1\right)\)

\(\Leftrightarrow2x^2+4x^2-4=6x^2+2x\)

\(\Leftrightarrow-4-2x=0\Leftrightarrow x=-2\)

c, \(2x\left(5-3x\right)+2x\left(3x-5\right)-3\left(x-7\right)=4\)

\(\Leftrightarrow10x-6x^2+6x^2-10x-3x+21=4\)

\(\Leftrightarrow-3x+17=0\Leftrightarrow x=\frac{17}{3}\)

d, \(5x\left(x+1\right)-4x\left(x+2\right)=1-x\)

\(\Leftrightarrow5x^2+5x-4x^2-8x=1-x\)

\(\Leftrightarrow x^2-3x-1+x=0\Leftrightarrow x^2-2x-1=0\)

\(\Leftrightarrow x^2-2x+1-2=0\Leftrightarrow\left(x-1\right)^2=2\)

\(\Leftrightarrow\orbr{\begin{cases}x-1=\sqrt{2}\\x-1=-\sqrt{2}\end{cases}\Leftrightarrow\orbr{\begin{cases}x=\sqrt{2}+1\\x=-\sqrt{2}+1\end{cases}}}\)

a)\(2x\left(x+1\right)-3-2x=5\)

\(\Leftrightarrow2x^2+2x-3-2x=5\)

\(\Leftrightarrow2x^2=8\)

\(\Leftrightarrow x^2=4=\left(-2\right)^2=2^2\)

              \(\Rightarrow x=2;-2\)

b)\(2x\left(3x+1\right)+\left(4-2x\right)=7\)

\(\Leftrightarrow6x^2+2x+4-2x=7\)

\(\Leftrightarrow6x^2+4=7\)

\(\Leftrightarrow6x^2=3\)

\(\Leftrightarrow x^2=\frac{1}{2}=-\sqrt{\frac{1}{2}}=\sqrt{\frac{1}{2}}\)

c)\(\left(x-3\right)^3-\left(x-3\right)\left(x^2+3x+9\right)+6\left(x-1\right)^2=6\)

\(\Leftrightarrow x^3-9x^2+27x-27-x^3+27+6\left(x^2-2x+1\right)=6\)

\(\Leftrightarrow-3x^2+27x+6x^2-12x+6=6\)

​\(\Leftrightarrow-3x^2+27x+6x^2-12x+6=6\)​​

​\(\Leftrightarrow3x^2+15x=0\)

\(\Leftrightarrow3x\left(x+5\right)=0\)

         \(\Rightarrow\orbr{\begin{cases}3x=0\\x+5=0\end{cases}\Rightarrow}\orbr{\begin{cases}x=0\\x=-5\end{cases}}\)

a)4×(x-5)-(x-1)×(4x-3)=5

=>4x-20-4x²+7x-3-5=0

=>-4x²+11x-28=0

=>-4(x²-\(\frac{11x}{4}\)+7)=0

=>\(-4\left(x-\frac{11}{8}\right)^2-\frac{327}{16}< 0\)

=>vô nghiệm

b) (3x-4)(x-2)=3x(x-9)-3

=>3x²-10x+8=3x²-27x-3

=>17x=-11

=>x=-11/17

c)(x-5)×(x-4)-(x+1)×(x-2)=7

=>x²-9x+20-x²+x+2=7

=>22-8x=7

=>-8x=-15

=>x=8/15

d)(2x-1)×(x-2)-(x+3)×(2x-7)=3

=>2x²-5x+2-2x²+x+21=3

=>23-4x=3

=>-4x=-20

=>x=5

Noob ơi, bạn phải đưa vào máy tính ý solve cái là ra x luôn, chỉ tội là đợi hơi lâu

a, 4.(18 - 5x) - 12(3x - 7) = 15(2x - 16) - 6(x + 14) 

=> 72 - 20x - 36x + 84 = 30x - 240 - 6x - 84

=> (72 + 84) + (-20x - 36x) = (30x - 6x) + (-240 - 84) 

=> 156 -  56x = 24x - 324 

=>  24x + 56x = 324 + 156 

=> 80x = 480 

=> x = 480 : 80 =  6 

Vậy x = 6 

b, 5(3x + 5) - 4(2x - 3) = 5x + 3(2x + 12) + 1 

=> 15x + 25 - 8x + 12 = 5x + 6x + 36 + 1 

=> (15x - 8x) + (25 + 12) = 11x + 37 

=> 7x + 37 = 11x + 37 

=> 11x - 7x = 0 

=>  x = 0