`@` `\text {Ans}`

`\downarrow`

`c)`

`(34 - 2x)(2x - 6) = 0`

`=>`\(\left[{}\begin{matrix}34-2x=0\\2x-6=0\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}2x=34\\2x=6\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=34\div2\\x=6\div2\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=17\\x=3\end{matrix}\right.\)

Vậy, `x \in {17; 3}`

`d)`

`(2019 - x)(3x - 12) = 0`

`=>`\(\left[{}\begin{matrix}2019-x=0\\3x-12=0\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019-0\\3x=12\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019\\x=12\div3\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019\\x=4\end{matrix}\right.\)

Vậy, `x \in {2019; 4}.`

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

1) Ta có: \(x^2-4x+4=0\)

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

\(\Leftrightarrow x-2=0\)

hay x=2

Vậy: S={2}

`@` `\text {Ans}`

`\downarrow`

`c)`

`( 34 - 2x ) * ( 2x - 6 ) = 0`

`=>`\(\left[{}\begin{matrix}34-2x=0\\2x-6=0\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}2x=34-0\\2x=0+6\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}2x=34\\2x=6\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=34\div2\\x=6\div2\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=17\\x=3\end{matrix}\right.\)

Vậy, `x \in {17; 3}`

`d)`

\(\left(2019-x\right)\left(3x-12\right)=0\)

`=>`\(\left[{}\begin{matrix}2019-x=0\\3x-12=0\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019-0\\3x=0+12\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019\\3x=12\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019\\x=12\div3\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=2019\\x=4\end{matrix}\right.\)

Vậy,` x \in {2019; 4}`

^{p/s: Bài này hnhu mk làm r mà ạ?}

a) 5.(x-7)=0

=> x-7 = 0

x = 7

b) 34.(2x-6)=0

=> 2x -6 = 0

2x = 6

x = 3

5 (x - 7) = 0

=> x - 7 = 0

=> x = 7

34 (2x - 6) = 0

=> 2x - 6 = 0

=> 2x = 6

=> x = 3

5 (x - 7) = 0

<=> x-7=0

<=> x=7

34 (2x - 6) = 0

<=> 2x-6=0

<=> 2x=6

<=> x=3

bấm máy tính được luôn đó bạn

nói chứ tính giá trị của trị tuyệt đối rồi đặt 2 trường hợp là x nhỏ hơn 17 và x lớn hơn 17.  giải ra nghiệm

ahihi

34(2x-6)=0

2x-6=0

2x=6

x=3

=.= hok tốt!!

34(2x - 6) = 0

     2x - 6  = 0 : 34

      2x - 6 = 0

             2x = 0 + 6

             2x = 6

               x = 6: 2 

                x = 3

Chúc bạn học tốt!

Thân!

34(2x-6)=0

    (2x-6)=0:34

    (2x-6) =0

     2x      =0+6

     2x      =6

       x      =6:2 

       x       =3

mình gửi lộn

b) 17x – ( -16x – 37) = 2x + 43

-> 33x +37 =2x +43

->31x=6 

-> x= 6/31

c) -2x –3. (x – 17) = 34 – 2(-x + 25)

->-5x + 51= 2x-16

->7x= 67

x= 67/7

d) (-x - 6) (x + 9) = 0

  Ta có (-x-6)= 0 hoặc (x+9)=0

-> x=-6 hoặc x=-9

b) 17x – ( -16x – 37) = 2x + 43

\(\Leftrightarrow\)17x+16x+37=2x+43

\(\Leftrightarrow\)33x+37-2x-43=0

\(\Leftrightarrow\)31x=6

\(\Leftrightarrow\)x=31/6

c) -2x –3. (x – 17) = 34 – 2(-x + 25)

\(\Leftrightarrow\)-2x-3x-51=34+2x-50

\(\Leftrightarrow\)-5x-51=-16+2x

\(\Leftrightarrow\)-5x-51+16-2x=0

\(\Leftrightarrow\)-7x=35

\(\Leftrightarrow\)x=-5

d) (-x - 6) (x + 9) = 0

\(\hept{\frac{-x-6=0}{x+9=0}}\Leftrightarrow\)\(\hept{\begin{cases}x=-6\\x=-9\end{cases}}\)

a) \(5\left(x-7\right)=0\)

\(\Rightarrow x-7=0\)

\(\Rightarrow x=7\)

b) \(25\left(x-4\right)=0\)

\(\Rightarrow x-4=0\)

\(\Rightarrow x=4\)

c) \(\left(34-2x\right)\left(2x-6\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}34-2x=0\\2x-6=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}2x=34\\2x=6\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=17\\x=3\end{matrix}\right.\)

d) \(\left(2019-x\right)\left(3x-12\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}2019-x=0\\3x-12=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=2019\\3x=12\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=2019\\x=\dfrac{12}{3}=4\end{matrix}\right.\)

e) \(57\left(9x-27\right)=0\)

\(\Rightarrow9x-27=0\)

\(\Rightarrow9\left(x-3\right)=0\)

\(\Rightarrow x-3=0\)

\(\Rightarrow x=3\)

a) 5.(x-7)=0⇔x-7=0⇔x=7

b) 25(x-4)=0⇔x-4=0⇔x=4

c) (34-2x).(2x-6)=0

⇔ 34-2x=0 hoặc 2x-6=0

⇔2x=34 hoặc 2x=6

⇔ x=17 hoặc x=3

d) (2019-x).(3x-12)=0

⇔ 2019-x=0 hoặc 3x-12=0

⇔ x=2019 hoặc x=4

e) 57.(9x-27)=0

⇔ 9x-27=0

⇔ x=3

f) 25+(15-x)=30

⇔ 15-x=5

⇔ x=10

g) 43-(24-x)=20

⇔ 24-x=23

⇔ x=1

h) 2.(x-5)-17=25

⇔ 2(x-5)=42

⇔x-5=21

⇔ x=26

i) 3(x+7)-15=27

⇔ 3(x+7)=42

⇔ x+7=14

⇔ x=7

j) 15+4(x-2)=95

⇔ 4(x-2)=80

⇔ x-2=20

⇔ x=22

k) 20-(x+14)=5

⇔ x+14=15

⇔ x=1

l) 14+3(5-x)=27

⇔ 3(5-x)=13

⇔ 5-x=13/3

⇔ x=5-13/3

⇔ x=2/3