TB
1
K
Khách
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Các câu hỏi dưới đây có thể giống với câu hỏi trên
9 tháng 7 2023
`@` `\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}`
`e) `
`57 . ( 9x - 27 ) = 0`
`=>`\(9x-27=0\div57\)
`=> 9x - 27 = 0`
`=> 9x = 27`
`=> x = 27 \div 9`
`=> x = 3`
Vậy, `x = 3`
`f)`
`25 + ( 15 - x ) = 30`
`=> 15 - x = 30 - 25`
`=> 15 - x = 5`
`=> x = 15 -5 `
`=> x = 10`
Vậy, `x = 10`
`g) `
`43 - ( 24 - x ) = 20`
`=> 24 - x = 43 - 20`
`=> 24 - x = 23`
`=> x = 24 - 23`
`=> x = 1`
Vậy, `x = 1`
`h) `
`2 . ( x - 5 ) - 17 = 25`
`=> 2 ( x - 5) = 25+17`
`=> 2 ( x - 5) = 42`
`=> x - 5 = 42 \div 2`
`=> x - 5 = 21`
`=> x = 21 + 5`
`=> x = 26`
Vậy, `x = 26`
`i)`
`3 . ( x + 7 ) - 15 = 27`
`=> 3(x + 7) = 27 + 15`
`=> 3(x + 7) = 42`
`=> x +7 = 42 \div 3`
`=> x + 7 = 14`
`=> x = 14 - 7`
`=> x = 7`
Vậy, `x = 7`
`j)`
`15 + 4 . ( x - 2 ) = 95`
`=> 4(x - 2) = 95 - 15`
`=> 4(x - 2) = 80`
`=> x - 2 = 80 \div 4`
`=> x - 2 = 20`
`=> x = 20 + 2`
`=> x = 22`
Vậy, `x = 22`
`k)`
`20 - ( x + 14 ) = 5`
`=> x + 14 = 20 - 5`
`=> x + 14 = 15`
`=> x = 15 - 14`
`=> x = 1`
Vậy, `x = 1`
`l) `
`14 + 3 . ( 5 - x ) = 27`
`=> 3(5 - x) = 27 - 14`
`=> 3(5 - x) = 13`
`=> 5 - x = 13 \div 3`
`=> 5 - x = 13/3`
`=> x = 5- 13/3`
`=> x = 2/3`
Vậy, `x = 2/3.`
`@` `\text {Kaizuu lv uuu}`
H9
HT.Phong (9A5)
CTVHS
8 tháng 7 2023
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) \(57\left(9x-27\right)=0\)
\(\Rightarrow9x-27=0\)
\(\Rightarrow9\left(x-3\right)=0\)
\(\Rightarrow x-3=0\)
\(\Rightarrow x=3\)
8 tháng 7 2023
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
6 tháng 10 2018
a)2019-5{70+9[37-(32+1)]}=2019-5{70+9[37-33]}=2019-5{70+9.4}=2019-5.106=2019-530=1489
b)3[25-(9+8)]-25(8+1)=3[25-17]-25.9=3.8-225=-201
T
3
P2
20 tháng 12 2019
a)
\(-68+\left(-72\right)+2017+\left(-28\right)+168.\)
\(=\left(-68+168\right)+\left(-28-72\right)+2017.\)
\(=\left(168-68\right)+\text{ }\left[-\left(72+28\right)\right]+2017.\)
\(=100+\left(-100\right)+2017.\)
\(=100-100+2017.\)
\(=2017\)
b)
\(\left|-28\right|+\left(129-182+99\right)\)\(-\left(129+199-182\right)\)
\(=28+129-182+99\)\(-129-199+182.\)
\(=28+\left(129-129\right)+\left(182-182\right)\)\(-\left(199-99\right)\)
\(=28+0+0-100.\)
\(=-\left(100-28\right)\)
\(=-72\)
c)
\(17\left(-83\right)+18\times83.\)
\(=-17\left(83\right)+18\left(83\right)\)
\(=83\left[18+\left(-17\right)\right]\)
\(=83\left(18-17\right)\)
\(=83\left(1\right)\)
\(=83\)
d)
\(2018^0-\left(15^2\div\left[175+\left(2^3\times5^2-6\times25\right)\right]\right).\text{ }\)
\(=1-\left(15^2\div\left[175+\left(8\times25-6\times25\right)\right]\right)..\)
\(=1-\left(15^2\div\left[175+\left(25\left[8-6\right]\right)\right]\right)\)
\(=1-\frac{15^2}{175+\left(25\times2\right)}.\)
\(=1-\frac{15^2}{175+50}\)
\(=1-\frac{225}{225}\)
\(=1-1\)
\(=0\)
Học tốt
LT
22 tháng 11 2018
a) \(96 : 2^4 + 3^2 - 2018^0 \)
= 96 : 16 + 9 - 1
= 6 + 9 - 1
= 15 - 1
= 14
b) 32 . 77 + 33 . 24 - 32
= 2541 + 768 - 32
= 3309 - 32
= 3327
c) \({2 . 3^2 + [144 - 5^2 . (15 - 169 : 13)]} - 1^2019\)
1^2019 nha bạn
= 2 . 9 + [144 - 25 . (15 - 169 : 13)]}- 1
= 2 . 9 + [144 - 25 . (15 - 13)]}- 1
= 2 . 9 + [144 - 25 . 2]}- 1
= 2 . 9 + [144 - 50]}- 1
= 2 . 9 + 94 - 1
= 18 + 94 - 1
= 112 - 1
= 111
d) 5^27 . 5 : 5^25 + -125 = 0
-150 bạn nha