1) \(\Rightarrow\left[{}\begin{matrix}x=-3\\x=5\end{matrix}\right.\)

2) \(\Rightarrow5\left(x-2\right).3\left(x+2\right)=0\Rightarrow\left[{}\begin{matrix}x=2\\x=-2\end{matrix}\right.\)

3) \(\Rightarrow2\left(x-4\right)\left(x-7\right)=0\Rightarrow\left[{}\begin{matrix}x=4\\x=7\end{matrix}\right.\)

a) 

x+3=0⇔x=-3

x-5=0⇔x=5

b

5x-10=0⇔x=2

3x+6=0⇔x=-2

c) 

x-4=0⇔x=4

2x-14=0⇔x=7

1) ⇒[x=−3x=5⇒[

        [x=−3x=5

2) ⇒5(x−2).3(x+2)=0⇒[x=2x=−2⇒5(x−2).3(x+2)=0⇒[x=2x=−2

3) ⇒2(x−4)(x−7)=0⇒[x=4x=7

`x-1/9 =8/3`

`=>x=8/3 +1/9`

`=> x= 24/9 +1/9`

`=>x= 25/9`

Vậy `x=25/9`

__

`x-2/20=-5/2-x`

`=>x+x=-5/2 +2/20`

`=> 2x= -50/20 +2/20`

`=> 2x= -48/20`

`=> x= -12/5:2`

`=>x=-12/5 xx1/2`

`=>x= -12/10`

`=>x= -6/5`

Vậy `x=-6/5`

`@` `\text {Ans}`

`\downarrow`

`a)`

Đề là \(\dfrac{x-1}{9}=\dfrac{8}{3}\) phải hongg bạn?

\(\dfrac{x-1}{9}=\dfrac{8}{3}\)

`=>` `(x-1)3 = 8*9`

`=> (x-1)3=72`

`=> x-1=72 \div 3`

`=> x-1=24`

`=> x=25`

`b)`

\(\dfrac{x-2}{20}=\dfrac{-5}{2-x}\)

`=>` `(x-2)(2-x)=20*(-5)`

`=> (x-2)(2-x)=-100`

`=> -[(x-2)(x-2)]=-100`

`=> -(x-2)^2 = -100`

`=> (x-2)^2 = 100`

`=> (x-2)^2 = (+-10)^2`

`=>`\(\left[{}\begin{matrix}x-2=10\\x-2=-10\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=12\\x=-8\end{matrix}\right.\)

Ta có : |x - 2| ; |x - 5| ; |x - 18| ≥0∀x∈R≥0∀x∈R

=> |x - 2| + |x - 5| + |x - 18|  ≥0∀x∈R≥0∀x∈R

=> D có giá trị nhỏ nhất khi x = 2;5;18

Mà x ko thể đồng thời nhận 3 giá trị

Nên GTNN của D là : 16 khi x = 5   ok nha bạn

x^2/x-1 = x^2-4x+4/x-1 + 4 = (x-2)^1/x-1 + 4 >= 4

Dấu "=" xảy ra <=> x-2 = 0 <=> x = 2 (tm)

Vậy GTNN của x^2/x-1 = 4 <=> x= 2

k mk nha

TL

\(\frac{11}{4}\)

Xin k

Nhớ k

HT

\(\Leftrightarrow x:3+367\cdot\left(-2\right)=-60\)

=>x:3=674

hay x=2022

x= 2022

a) \(\dfrac{13}{20}+\dfrac{3}{5}+x=\dfrac{5}{6}\)

\(\Rightarrow\dfrac{5}{4}+x=\dfrac{5}{6}\)

\(\Rightarrow x=\dfrac{5}{6}-\dfrac{5}{4}\)

\(\Rightarrow x=\dfrac{-5}{12}\)

b) \(x+\dfrac{1}{3}=\dfrac{2}{5}-\dfrac{-1}{3}\)

\(\Rightarrow x+\dfrac{1}{3}=\dfrac{11}{15}\)

\(\Rightarrow x=\dfrac{11}{15}-\dfrac{1}{3}\)

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

c)\(\dfrac{-5}{8}-x=\dfrac{-3}{20}-\dfrac{-1}{6}\)

\(\dfrac{-5}{8}-x=\dfrac{1}{60}\)

\(\Rightarrow x=\dfrac{-5}{8}-\dfrac{1}{60}\)

\(\Rightarrow x=\dfrac{-77}{120}\)

d) \(\dfrac{3}{5}-x=\dfrac{1}{4}+\dfrac{7}{10}\)

\(\Rightarrow\dfrac{3}{5}-x=\dfrac{19}{20}\)

\(\Rightarrow x=\dfrac{3}{5}-\dfrac{19}{20}\)

\(\Rightarrow x=\dfrac{-7}{20}\)

e) \(\dfrac{-3}{7}-x=\dfrac{4}{5}+\dfrac{-2}{3}\)

\(\Rightarrow\dfrac{-3}{7}-x=\dfrac{2}{15}\)

\(\Rightarrow x=\dfrac{-3}{7}-\dfrac{2}{15}\)

\(\Rightarrow x=\dfrac{-59}{105}\)

g) \(\dfrac{-5}{6}-x=\dfrac{7}{12}+\dfrac{-1}{3}\)

\(\Rightarrow\dfrac{-5}{6}-x=\dfrac{1}{4}\)

\(\Rightarrow x=\dfrac{-5}{6}-\dfrac{1}{4}\)

\(\Rightarrow x=\dfrac{-13}{12}\)

a) 297 : ( x - 5 ) = 33

               x - 5    = 297 : 33

              x - 5     = 9

              x          = 9 + 5

              x          = 14

a, 297 : (x-5) = 33

              x-5   = 297 : 33

              x-5   = 9

              x      = 9 + 5

              x      = 14

b, x*5 + x*7 + x*8 = 680

    x*(5+7+8) = 680

    x*20 = 680

    x       = 680 : 20

    x       = 34

\(x\times5+x\times7+x\times8=680\)

\(x\times\left(5+7+8\right)=680\)

\(x\times20=680\)

\(x=680:20\)

\(x=34\)

x/-30+1,75=-5/9:4/3

=>x/-30+7/4=-5/12

=>x/-30=-13/6

=>x.6=-30.-13

=>x.6=390

=>x=65

vậy x=65.

bạn viết rõ ra phân số ra nha!

0,3625

\(\text{0,29 x 8 x 1,25 = ?}\)

\(0.29X8=2.32\)

\(2.32X1.25=\text{2.9}\)

0,29 x 8 x 1,25 

= 0.29 x 10

 = 2,9