\(\dfrac{x+1}{2x+1}=\dfrac{3}{5}\)
⇔\(5\left(x+1\right)=3\left(2x+1\right)\)
⇔\(5x+5=6x+3\)
⇔\(5x+5-6x-3=0\)
⇔\(-x+2=0\)
⇔\(-x=-2\)
⇔\(x=2\)
\(\dfrac{x+1}{2x+1}=\dfrac{3}{5}\)
⇔\(5\left(x+1\right)=3\left(2x+1\right)\)
⇔\(5x+5=6x+3\)
⇔\(5x+5-6x-3=0\)
⇔\(-x+2=0\)
⇔\(-x=-2\)
⇔\(x=2\)
Chứng minh rằng giá trị biểu thức sau không phụ thuộc vào giá trị của biến :
1) D= { 4x-2.(x-3) -3.[x-3(4-2x)+8]} . ( -3x) - (57x2 +54x)
2) E= x.(3x+12) -(7x-20) +x2.(2x-3) -x.( 2x2+5)
3) F= 5.(3x2-4y3)+[ 9.(2x2y3)-2.(x2-5y3)]-x2-21y2+100
\(\dfrac{x-3}{3}=\dfrac{2x+1}{5}\)
\(\dfrac{x+1}{22}=\dfrac{6}{x}\)
\(\dfrac{2x-1}{2}=\dfrac{5}{x}\)
\(\dfrac{2x-1}{21}=\dfrac{3}{2x+1}\)
\(\dfrac{2x+1}{9}=\dfrac{5}{x+1}\)
Tìm x
Bài tập: Rút gọn biểu thức
A=|x-2| + |3-x| +|2x-5|+|10-2x|
B=3|x-3|+2|4-x|+|x|
C=-6|x+1|-3|2x+1|+5|x-1|
D=-|x|+|3x-1|-|4x+1|+|x-9|
E=5|x-7|-2|2x-7|+3|x+5|-4|4-2x|
Tìm x biết : a) 2x+3/15 = 7/5. b) x-2/9 = 8/3. c) -8/x = -x/18 d) 2x+3/6 = x-2/5. e) x+1/22 = 6/x f) 2x-1/2 = 5/x g) 2x-1/21 = 3/2x+1 h) 10x+5/6 = 5/x+1
Tìm x biết
a,|x-1|+2x=3
b,|x+1|+|x+3|=10-4x
c,|x+1++3|x-2|-5|4-x|=13-2x
d,3|x-2|-2.|x+5|+4.|x-1|=9-7x
a) 1/x-1 + -2/3 x (3/4 - 6/5) = 5/2-2x
b) 3 - 2/2x-3 = 2/5 + 2/9-6x - 3/2
c) x/2 - 1/x = 1/12
Tìm x,biết
a)|x-1|+|x-3|=2x-1
b)|x+1|+|x-1|=0
c)|x+5|-|1-2x|=x
d)|x|-|2x+3|=x-1
e)|x|-|1-x|=x+|x-3|
g)|x-3|+|3x+4|=|2x+1|
h)|x-2|+|x-3|+|2x-8|=9
k)|x-1|+|x-3|+|x-5|+|x-7|=8
Giúp mình nha mình đang cần gấp
1) |x+5|+|x-3| =9
2) 2|x+2|+|4-x|=11
3)|7-x|-|2x-1|=5
4)|x-2|-|x-3|+|x-4|=1
Tìm x , mấy bạn giúp vs ạ .E có quàa
1 , | x - 9 | - x = 15 - ( -2) + |- 17|
2 , | 2x^2 + 1 | - 3x = 2x^2 - x + 5
3 , 3 - 5 . | x+1| = 24
4 , | 3-x | - 2x = 4
5 , | x+3| + | x-3 | + | x+6| = 6x - 18
6 , | x+2| + |x+3| = x
7 , | x-1| + |y-1| = 0