l3x-1l=l5-2xl
Bài 1 tìm x
c)3x - 3 + l2x-1l =0
d)l3x-1l = l5-2xl
(Dấu ll là giá trị tuyệt đối)
Tìm x biết:
a, l3x-1l+l1-3xl=6
b, l2x-1l+l1-2xl=8
á. Ta có /3x-1/=/1-3x/=>/3x-1/+/1-3x/=2/3x-1/=6 hay /3x-1/=3
Den day ban chia 2 TH : 3x-1=3 hoac 3x-1=-3
b. Tuong tu
l2x-1l+3x=2
l1-3xl-2x=4
3x-l2x+3l=1
4x+l3x-1l=2
5x-l1-2xl=5
Tìm x biết:
l2x-1l+3x=2
l1-3xl-2x=4
3x-l2x+3l=1
4x+l3x-1l=2
5x-l1-2xl=5
a) \(\left|2x-1\right|+3x=2\)
\(TH1\) \(2x-1+3x=2\) \(TH2\) \(2x-1+3x=-2\)
\(5x=3\) \(5x=-1\)
\(x=\frac{3}{5}\) \(x=\frac{-1}{5}\)
vậy \(x=\frac{3}{5}\) HOẶC \(x=\frac{-1}{5}\)
b) \(\left|1-3x\right|-2x=4\)
\(TH1\) \(1-3x-2x=4\) \(TH2\) \(1-3x-2x=-4\)
\(-5x=3\) \(-5x=-5\)
\(x=\frac{-3}{5}\) \(x=1\)
vậy \(x=\frac{-3}{5}\) HOẶC \(x=1\)
c) \(3x-\left|2x+3\right|=1\)
\(TH1\) \(3x-2x+3=1\) \(TH2\) \(3x-2x+3=-1\)
\(x=-2\) \(x=-4\)
vậy \(x=-2\) HOẶC \(x=-4\)
d) \(4x+\left|3x-1\right|=2\)
\(TH1\) \(4x+3x-1=2\) \(TH2\) \(4x+3x-1=-2\)
\(7x=3\) \(7x=-1\)
\(x=\frac{3}{7}\) \(x=\frac{-1}{7}\)
vậy \(x=\frac{3}{7}\) HOẶC \(x=\frac{-1}{7}\)
e) \(5x-\left|1-2x\right|=5\)
\(TH1\) \(5x-1-2x=5\) \(TH2\) \(5x-1-2x=-5\)
\(3x=6\) \(3x=-4\)
\(x=2\) \(x=\frac{-4}{3}\)
vậy \(x=2\) HOẶC \(x=\frac{-4}{3}\)
mk làm lun
1,
(1)= 2x-1+3x=2
= 5x-1=2
x= 3/5
(2) = -2x+1+3x = 2
= x+1=2
x= 1
2,
(1)= 1-3x-2x = 4
= 1-5x= 4
-5x= 3
x= -3/5
(2)= -1+3x -2x =4
= -1+x= 4
x= 5
3,
(1) 3-2x+3=1
= 3-2x+3=1
= 6-2x=1
=-2x= -5
x= 5/2
(2)= 3-2x-3=1
- -2x = 1
x= -1/2
4,
(1)=4x +3x -1 = 2
= 7x-1=2
= 7x=3
x= 3/7
(2)= 4x-3x+1=2
x+1=2
x=1
5,
(1) = 5x-1-2x=5
3x-1=5
= 3x=6
x= 2
(2)= 5x-1+2x=5
7x-1=5
7x=6
x= 6/7
chú ý (1) , (2) vì nó có 2 trg hợp lên mk ghi vậy
Tìm x và y biết
a. 2l2x-3l=1/2
b. 7,5-3l5-2xl=-4,5
c. l3x-4l+l5y+5l=0
d. lx+3l+lx+1l=3x
a) 2|2x-3| = 1/2
=> |2x-3| = 1/4
=> 2x-3 = 1/4 hoặc 2x-3 = -1/4
=> x = 13/8 hoặc x = 11/8
b) 7,5 - 3|5-2x| = -4,5
=> 3|5-2x| = 12
=> |5-2x| = 4
=> 5-2x = 4 hoặc 5-2x = -4
=> x = 1/2 hoặc x = 4,5
c) |3x-4| + |5y+5| = 0
=> 3x-4 = 0 hoặc 5y+5 = 0
=> x = 4/3 hoặc y = -1
d) |x+3| + |x+1| = 3x
=> x+3+ x+1 = 3x
=> 2x + 4 = 3x
=> x = 4
Rút gọn:
a)A=2.l3x-1l-l5-xl
b)B=2.I2x-1I-3.I2x+3I
a) + Với \(x< \frac{1}{3}\) thì |3x - 1| = 1 - 3x; |5 - x| = 5 - x
Ta có:
A = 2.(1 - 3x) - (5 - x)
A = 2 - 6x - 5 + x
A = -3 - 5x
+ Với \(\frac{1}{3}\le x< 5\) thì |3x - 1| = 3x - 1; |5 - x| = 5 - x
Ta có:
A = 2.(3x - 1) - (5 - x)
A = 6x - 2 - 5 + x
A = 7x - 7
+ Với \(x\ge5\) thì |3x - 1| = 3x - 1; |5 - x| = x - 5
Ta có:
A = 2.(3x - 1) - (x - 5)
A = 6x - 2 - x + 5
A = 5x + 3
Mọi người giúp mình giải bài này nha. THANHKS
lA(x)l=B(x)
1) l5xl=x-12
2) l7-xl=5x+1
3) l2x-3l+x=21
4) l4+2xl=-4x
5) l3x-1l+2=x
6) l2x-5l+x=2
7) l2x-5l=x+1
8) l3x-2l-1=x
9) l2x-1l+1=x
10) lx-5l+5=x
\(1,|5x|=x-12\)
\(\Rightarrow\orbr{\begin{cases}5x=x-12\\5x=12-x\end{cases}\Rightarrow}\orbr{\begin{cases}4x=-12\\6x=12\end{cases}\Rightarrow\orbr{\begin{cases}x=-3\\x=2\end{cases}}}\)
\(2,|7-x|=5x+1\)
\(\Rightarrow\orbr{\begin{cases}7-x=5x+1\\7-x=-5x-1\end{cases}\Rightarrow}\orbr{\begin{cases}6x=6\\4x=-8\end{cases}\Rightarrow}\orbr{\begin{cases}x=1\\x=-2\end{cases}}\)
\(3,|2x-3|+x=21\)
\(\Rightarrow|2x-3|=21-x\)
\(\Rightarrow\orbr{\begin{cases}2x-3=21-x\\2x-3=x-21\end{cases}\Rightarrow}\orbr{\begin{cases}3x=24\\x=-18\end{cases}\Rightarrow}\orbr{\begin{cases}x=8\\x=-18\end{cases}}\)
\(4,|4+2x|=-4x\)
\(\Rightarrow\orbr{\begin{cases}4+2x=4x\\4+2x=-4x\end{cases}\Rightarrow}\orbr{\begin{cases}2x=4\\-6x=4\end{cases}\Rightarrow}\orbr{\begin{cases}x=2\\x=-\frac{2}{3}\end{cases}}\)
\(5,|3x-1|+2=x\)
\(\Rightarrow|3x-1|=x-2\)
\(\Rightarrow\orbr{\begin{cases}3x-1=x-2\\3x-1=2-x\end{cases}\Rightarrow\orbr{\begin{cases}2x=-1\\4x=3\end{cases}\Rightarrow}\orbr{\begin{cases}x=-\frac{1}{2}\\x=\frac{3}{4}\end{cases}}}\)
\(6,|2x-5|+x=2\)
\(\Rightarrow|2x-5|=2-x\)
\(\Rightarrow\orbr{\begin{cases}2x-5=2-x\\2x-5=x-2\end{cases}\Rightarrow\orbr{\begin{cases}3x=7\\x=3\end{cases}\Rightarrow}\orbr{\begin{cases}x=\frac{7}{3}\\x=3\end{cases}}}\)
\(7,|2x-5|=x+1\)
\(\Leftrightarrow\orbr{\begin{cases}2x-5=x+1\\2x-5=-x-1\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}2x-x=1+5\\2x+x=-1+5\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=6\\3x=4\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=6\\x=\frac{4}{3}\end{cases}}\)
\(8,|3x-2|-1=x\)
\(\Leftrightarrow|3x-2|=x+1\)
\(\Leftrightarrow\orbr{\begin{cases}3x-2=x+1\\3x-2=-x-1\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}3x-x=1+2\\3x+x=-1+2\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}2x=3\\4x=1\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=\frac{3}{2}\\x=\frac{1}{4}\end{cases}}\)
Cho biểu thức B = l5 - 2xl - l3 + 2xl
a. Rút gọn B
b. Tìm x để B = -5
1) 2. I 2x-3 l = 1/2
2) I x+ \(\frac{4}{15}\)l - l-3,75l = -l- 2,15l
3) l 2+3xl- l4x-3 l=0
4) l3x-2l -1=x
5) lx+15l -15 =x
6) l7-2xl+ 7 =2x
7) lx-1l + lx+3l = x-1
Giúp mk với !!
1) 2. I2x-3l = 1/2
|2x-3| =1/2:2
|2x-3| =1/4
=>2x-3 =1/4 hoặc 2x-3 =-1/4
2x =1/4+3 2x =-1/4+3
2x =13/4 2x =11/4
x =13/4:2 x =11/4:2
x =13/8 x =11/8
vậy x=13/8 hoặc 11/8
tich dung cho minh nhe