![](https://rs.olm.vn/images/avt/0.png?1311)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) (x - 15) × 7 - 270 : 45 = 169
(x - 15) × 7 - 6 = 169
(x - 15) × 7 = 169 + 6
(x - 15) × 7 = 175
x - 15 = 175 : 7
x - 15 = 25
x = 25 + 15
x = 40
b) [(4x + 28) × 3 + 55] : 5 = 35
(4x + 28) × 3 + 55 = 35 × 5
(4x + 28) × 3 + 55 = 175
(4x + 28) × 3 = 175 - 55
(4x + 28) × 3 = 120
4x + 28 = 120 : 3
4x + 28 = 40
4x = 40 - 28
4x = 12
x = 12 : 4
x = 3
c) (455 × x : 2 × 6) : 5 = 31
455 × x : 2 × 6 = 31 × 5
455 × x : 2 × 6 = 155
x × 455 : 2 × 6 = 155
x × 1365 = 155
x = 155 : 1365
x = 31/273
d) 128 × x - 12 × x - 16 × x = 520800
(128 - 12 - 16) × x = 520800
100 × x = 520800
x = 520800 : 100
x = 5208
e) (x × 0,25 + 2022) × 2023 = (50 + 2022) × 2023
(x × 0,25 + 2022) × 2023 = 2072 × 2023
(x × 0,25 + 2022) × 2023 = 4191656
x × 0,25 + 2022 = 4191656 : 2023
x × 0,25 + 2022 = 2072
x × 0,25 = 2072 - 2022
x × 0,25 = 50
x = 50 : 0,25
x = 200
f) 4 × x + 100 = x + 280
4 × x - x = 280 - 100
(4 - 1) × x = 180
3 × x = 180
x = 180 : 3
x = 60
g) (x + 1) + (x + 2) + (x + 3) + ... + (x + 100) = 7450
x + 1 + x + 2 + x + 3 + ... + x + 100 = 7450
100 × x + 100 × 101 : 2 = 7450
100 × x + 5050 = 7450
100 × x = 7450 - 5050
100 × x = 2400
x = 2400 : 100
x = 24
![](https://rs.olm.vn/images/avt/0.png?1311)
` X xx 5,5 + X xx 3,5 + X = 98,6`
`X xx (5,5 + 3,5 + 1) = 98,6`
`X xx 10 = 98,6`
` X = 98,6 : 10`
`X = 9,86`
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(a,\left(x-15\right)\times7-270=169\times45\\ \left(x-15\right)\times7-270=7605\\ \left(x-15\right)\times7=7605+270\\ \left(x-15\right)\times7=7875\\ x-15=7875:7\\ x-15=1125\\ x=1125+15\\ x=1140\\ b,64-\left(34\times x-8\right)=4\\ 34\times x-8=64-4\\ 34\times x-8=60\\ 34\times x=60+8\\ 34\times x=68\\ x=68:34\\ x=2\)
![](https://rs.olm.vn/images/avt/0.png?1311)
Lời giải:
$x-\frac{x}{3}\times \frac{3}{2}=2-\frac{1}{2}$
$x-x\times \frac{1}{2}=\frac{3}{2}$
$x\times (1-\frac{1}{2})=\frac{3}{2}$
$x\times \frac{1}{2}=\frac{3}{2}$
$x=\frac{3}{2}: \frac{1}{2}=3$
![](https://rs.olm.vn/images/avt/0.png?1311)
a: \(x+\dfrac{3}{9}=\dfrac{7}{6}\cdot\dfrac{2}{3}\)
=>\(x+\dfrac{1}{3}=\dfrac{14}{18}=\dfrac{7}{9}\)
=>\(x=\dfrac{7}{9}-\dfrac{1}{3}=\dfrac{7}{9}-\dfrac{3}{9}=\dfrac{4}{9}\)
b: \(x-\dfrac{2}{3}=\dfrac{1}{8}:\dfrac{5}{4}\)
=>\(x-\dfrac{2}{3}=\dfrac{1}{8}\cdot\dfrac{4}{5}=\dfrac{1}{10}\)
=>\(x=\dfrac{1}{10}+\dfrac{2}{3}=\dfrac{3+20}{30}=\dfrac{23}{30}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
Tìm x, biết:
a.
75883-(31200+x)=999
31200+x =75883-999
31200+x= 74884
x = 74884-31200
x = 43684
b.
24 : ( x +1 ) = 8
x+1=24:8
x+1=3
x=3-1
x=2
c.
1+2+3+...+x=55
Dãy trên có số số hạng là:
(x−1):1+1=x−1+1=x
Ta có:
(x+1).x:2=55
(x+1).x=55.2
(x+1).x=110
(x+1).x=11.10
⇒x=10
a, ---> 31200 + x = 75883 - 999
---> 31200 + x = 74884
---> x = 74884 - 31200 = 43684
b, ---> x + 1 = 3
---> x = 2
c, Số số hạng là : x
Tổng = ( x + 1 ) * x : 2 = 55
---> x ( x + 1 ) = 110
---> 10 ( 10 + 1 ) = 110
---> x = 10
xin tiick
![](https://rs.olm.vn/images/avt/0.png?1311)
câu a bạn ghi thế thì mình chịu nha
b, \(24:\left(x+1\right)=8\)
\(x+1=24:8\)
\(x+1=3\)
\(x=3-1=2\)
c, \(1+2+3+...+x=55\)
SSH: \(\left(x-1\right):1+1=x\)
tổng: \(\left(x+1\right).x:2=55\)
\(\left(x+1\right).x=55.2\)
\(\left(x+1\right).x=110\)
\(\Rightarrow\left(x+1\right).x=11.10\)
vậy x=10
\(7x-8=718\\ \Rightarrow7x=718+8\\ \Rightarrow7x=726\\ \Rightarrow x=726:7\\\Rightarrow x=\dfrac{726}{7}\) \(246-3\left(x+2\right)=120\\ \Rightarrow3\left(x+2\right)=246-120\\ \Rightarrow3\left(x+2\right)=126\\ \Rightarrow x+2=126:3\\ \Rightarrow x+2=42\\ \Rightarrow x=42-2=40\)
tôi ko biết