Ta có | x - 7 | + 2x + 5 = 0
⇔ | x - 7 | = - 5 - 2x
⇔\(\left[{}\begin{matrix}x-7=-5-2x\\x-7=2x+5\end{matrix}\right.\)
⇔ \(\left[{}\begin{matrix}x+2x=-5+7\\x-2x=5+7\end{matrix}\right.\)
⇔ \(\left[{}\begin{matrix}3x=2\\-x=12\end{matrix}\right.\)
⇔\(\left[{}\begin{matrix}x=\frac{2}{3}\\x=-12\end{matrix}\right.\)
Vậy \(x\in\left\{\frac{2}{3};-12\right\}\)
Học tốt
Chiyuki Fujito
Tìm x biết :
a) | 2x - 1 | = 4
b) -3 | 2x | + | 5 - x | = 1
c) 2^x + 3 = 2^x - 1 = 15/64
d) | -3 + 5 | = x
e) ( x - 1 )^100 + ( x - y )^98 = 0
f) ( x - 7 )^x + 1 - ( x - 7 )^x + 5 = 0
Tìm x biết:
a. (x - 2).(x + 3/4) > 0
b. (2x - 5).(1 - 3x) > 0
c. (3 - 2x).(x + 1) < 0
d.(5x + 11).(7 - x) < 0
Tìm x,y biết :
1 ) | 4 - x | + | 2y +1 | = 0
2) | x - 3 | = | 5 - 2x |
|x-3| + |y-2x | =0
|x| + 3|2x -x ² | =0
|5x ² -5 | + 4|y-7 | =0
||x +1 | + |y-5 |=0
|x ² -1| + |y-1| =0
|x-1 | +|x ²-x |=0
tìm x biết
a, \(3\left(x-2\right)-4\left(2x+1\right)-5\left(2x+3\right)=50\)
b, \(\left(x-7\right)^5-\left(x-7\right)^3=0\)
tìm x
a, | 5/4x - 7/2 | - | 5/8x + 3/5 | = 0
b, 21/5 + 3 : | x/4 - 2/3 | = 6
c,| 9 + x | = 2x
d, | 2x - 3 | + x = 21
e, | 7 - 2x | + 7 = 2x
f, | -x + 2/5 | + 1/2 = 3,5
G, | 3x - 4 | + 4 = 3x
Tìm x,biết:
1) |x+2| + |x-5| = 7
2) |x-7| + 2x+5 =6
3) |2x + 1| +|x+3| = 4x
4) |x2 -2x| = x
5) |2x+3| = x+2
6) |5x-4 |= |x+2|
7) |x-2| - |2x - 3| - x = 2
Tìm x;y;z biết:
a) 2017-lx-2017l=x
b) (2x-5)2018+(3y-7)2020+lx+y+zl=0
Tìm x, biết:
1) \(\left|4x\right|=3x+12\) 7) \(\left|5x\right|-3x-2=0\)
2) \(\left|2x+4\right|=2x-5\) 8) \(x-5x+\left|-2x\right|-3=0\)
3)\(\left|x+3\right|=3x-1\) 9) \(\left|3-x\right|+x^2-\left(4+x\right)x=0\)
4) \(\left|x-4\right|+3x=5\)
5)\(\left|x-5\right|=3x\)
6) \(\left|x+2\right|=2x-10\)
