Tìm x :
|5x - 2| < 13tìm x
|5x-2|<13
Tìm x:
1, |5x+13|=2x-7
2,|2x|+|3x-8|-|4x+1|=5x-2
3, |x+1|+|x-3|+|x-10|=20
\(\left|5x+13\right|=2x-7\)
khi \(x>\frac{7}{2}\), biểu thức có dạng:
\(\orbr{\begin{cases}5x+13=2x-7\\5x+13=7-2x\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}3x=-20\\7x=-6\end{cases}\Rightarrow\orbr{\begin{cases}x=-\frac{20}{3}\\x=-\frac{6}{7}\end{cases}}}\)
tìm x:5x+2016=2006
2(x-4)-(x+5)=-13
tìm x:5x+2016=2006
2(x-4)-(x+5)=-13
5x+2016 = 2006 => 5x = 2006 - 2016 = -10 => x = -10 : 5 = -2
2(x-4)-(x+5) = 2x-8-x-5 = (2x-x)-(8+5) = x-13 = -13 => x = -13+13 = 0
\(5x+2016=2006\)
\(\Rightarrow5x=2006-2016\)
\(\Rightarrow5x=-10\)
\(\Rightarrow x=-10:5\)
\(\Rightarrow x=-2\)
\(2\left(x-4\right)-\left(x+5\right)=-13\)
\(\Rightarrow2x-8-x-5=-13\)
\(\Rightarrow x=-13+8+5\)
\(\Rightarrow x=0\)
Tìm x ∈ N biết:
a, x - 3 : 2 = 5 14 : 5 12
b, 30 : x - 7 = 15 19 : 15 18
c, x 70 = x
d, 2 x + 1 3 = 9 . 81
e, 5 x + 5 x + 2 = 650
f, 4 x - 1 2 = 25 . 9
a, x - 3 : 2 = 5 14 : 5 12
=> x - 3 : 2 = 5 2
=> x - 3 : 2 = 25
=> x – 3 = 25
=> x = 53
b, 30 : x - 7 = 15 19 : 15 18
=> 30 : x - 7 = 15
=> x – 7 = 2
=> x = 9
c, x 70 = x
=> x 70 - x = 0
=> x ( x 69 - 1 ) = 0
=>
d, 2 x + 1 3 = 9 . 81
=> 2 x + 1 3 = 9 3
=> 2x + 1 = 9
=> x = 4
e, 5 x + 5 x + 2 = 650
=> 5 x 1 + 5 2 = 650
=> 5 x . 26 = 650
=> 5 x = 25
=> x = 2
f, 4 x - 1 2 = 25 . 9
=> 4 x - 1 2 = 5 2 . 3 2
=> 4 x - 1 2 = 15 2
=> 4x – 1 = 15
=> x = 4
Tìm x ∈ N biết:
a) x - 3 : 2 = 5 14 : 5 12 . b) 30 : x - 7 = 15 19 : 15 18 . c) x 70 = x .
d) 2 x + 1 3 = 9 . 81 . e) 5 x + 5 x + 2 = 650 . f) 4 x - 1 2 = 25 . 9
Tìm x thuộc Z . Biết / 5x- 2 / < hoặc = 13
tìm x thuộc Z biết |5x-2| _< 13
tìm x ;
1. -5x - 9 = 5 - x
2. 2\(^{\left(x-5\right)}\) \(^{\left(x+2\right)}\) = 1
3. 2\(^x\) + 2 \(^{x+3}\) = 144
1: =>-4x=14
=>x=-7/2
2: =>(x-5)(x+2)=0
=>x=5 hoặc x=-2
3: =>2^x*9=144
=>2^x=16
=>x=4