![](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 + 30% = -1,3
suy ra: x + 3/10 = -13/10
x = -13/10 - 3/10
x = -8/5
b) x - 25% x = 1/2
suy ra : 1x -1/4x = 1/2
x(1-1/4) = 1/2
x = 1/2 : 3/4
x= 2/3
![](https://rs.olm.vn/images/avt/0.png?1311)
a) x/7 = 6/21
x/7 = 2/7
=>x=2
b)2/3x -1/2=1/10
2/3x = 1/10+1/2
2/3x = 3/5
x=3/5:2/3
x=9/10
c)1/4+1/3 : x = -5
d)3x+17=2
đ)2/3x +1/4 =7/12
2x+3/10= 11/6 . 6/11
x : 4 1/3 = -2,5
![](https://rs.olm.vn/images/avt/0.png?1311)
a) (2x - 3)(6 - 2x) = 0
=> \(\left[{}\begin{matrix}2x-3=0\\6-2x=0\end{matrix}\right.=>\left[{}\begin{matrix}2x=3\\2x=6\end{matrix}\right.=>\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=3\end{matrix}\right.\)
b) \(5\dfrac{4}{7}:x=13=>\dfrac{39}{7}:x=13=>x=\dfrac{39}{7}:13=>x=\dfrac{3}{7}\)
c) \(2x-\dfrac{3}{7}=6\dfrac{2}{7}=>2x-\dfrac{3}{7}=\dfrac{44}{7}=>2x=\dfrac{47}{7}=>x=\dfrac{47}{14}\)
d) \(\dfrac{x}{5}+\dfrac{1}{2}=\dfrac{6}{10}=>\dfrac{x}{5}=\dfrac{6}{10}-\dfrac{1}{2}=>\dfrac{x}{5}=\dfrac{1}{10}=>x.10=5=>x=\dfrac{1}{2}\)
e) \(\dfrac{x+3}{15}=\dfrac{1}{3}=>\left(x+3\right).3=15=>x+3=5=>x=2\)
![](https://rs.olm.vn/images/avt/0.png?1311)
5)
để \(\frac{5x-3}{x+1}\)là số nguyên
\(5x-3⋮x+1\)
\(x+1⋮x+1\)
\(\Rightarrow5\left(x+1\right)⋮x+1\)
\(5x-3-\left(5x-5\right)⋮x+1\)
\(-2⋮x+1\)
\(\Rightarrow x+1\inƯ\left(2\right)=\left\{\pm1;\pm2\right\}\)
x+1 | 1 | -1 | 2 | -2 |
x | 0 | -2 | 1 | -3 |
Vậy \(x\in\left\{0;-2;1;-3\right\}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) 2x + 1 = 3
2x = 2
x = 1
b) ( 2x - 5 ) + 17 = 6
( 2x - 5 ) = 6 - 17
( 2x - 5 ) = -11
2x = -11 + 5
2x = -6
x = -3
c) 10 - 2 x ( 4 - 3x ) = -4
2 x ( 4 - 3x ) = 14
4 - 3x = 7
3x = -3
x = -1
![](https://rs.olm.vn/images/avt/0.png?1311)
a) 2(x-6) + 3(x-6)=54
=> 2x-12+3x-18=54
=>5x-30=54
=>5x=84
=>x=16,8
b)2(3x+6)+3(x+4)=30
=> 6x+12+3x+12=30
=>9x+24=30
=>9x=6
=>x= 2/3
HỌC TỐT ^-^
a) 2(x-6)+3(x-6)=54
(2+3).(x-6) = 54
5(x-6) = 54
5x - 5.6 = 54
5x - 30 = 54
5x = 24
x = 24 : 5 ( Câu này dư dư bạn ạ, bạn xem lại đề nhé )
b) 2(3x+6)+3(x+4)=30
6x + 12 +3x + 12= 30
9x + 24 = 30
9x = 6 ( Lại dư bạn ơi )
Vậy là cả hai câu dư hết bạn nhé, xin lỗi bạn.
![](https://rs.olm.vn/images/avt/0.png?1311)
Tìm số nguyên x, biết:
1) -16 + 23 + x = - 16
7+x=-16
x=-16-7
x=-23
2) 2x – 35 = 15
2x=15+35
2x=50
x=50:2
x=25
3) 3x + 17 = 12
3x=12-17
3x=-5
x=-5/3
4) (2x – 5) + 17 = 6
2x-5=6-17
2x-5=-11
2x=-11+5
2x=-6
x=-6:2
x=-3
5) 10 – 2(4 – 3x) = -4
2(4-3x)=10-(-4)
2(4-3x)=14
4-3x=14:2
4-3x=7
3x=4-7
3x=-3
x=-3:3
x=-1
6) - 12 + 3(-x + 7) = -18
3(-x+7)=-18-(-12)
3(x+7)=-6
x+7=-6:3
x+7=-2
x=-2-7
x=-9