Tìm x:
b, 15 - 3 |2x - 1| = 6
c, 2 |x| - 7 = 27
Ai giúp e vs!
Tìm x:
b) x-3 ⋮ x+1
C) 2x+1 ⋮ 3x-2
\(b,\Rightarrow x+1-4⋮x+1\\ \Rightarrow x+1\inƯ\left(4\right)=\left\{-4;-2;-1;1;2;4\right\}\\ \Rightarrow x\in\left\{-5;-3;-2;0;1;3\right\}\\ c,\Rightarrow3\left(2x+1\right)-2\left(3x-2\right)⋮3x-2\\ \Rightarrow6x+3-6x+4⋮3x-2\\ \Rightarrow7⋮3x-2\\ \Rightarrow3x-2\inƯ\left(7\right)=\left\{-7;-1;1;7\right\}\\ \Rightarrow x\in\left\{-\dfrac{5}{3};\dfrac{1}{3}1;3\right\}\)
15-(2x-3)=6
(x-2).3=32
(x+7)-25=13
450:(x-19)=50
mng giúp e vs ạ !
c: \(\Leftrightarrow x+7=38\)
hay x=31
15-(2x-3)=6 (x-2).3=32
⇔ 2x-3=9 ⇔(x-2).3=9
⇔ 2x=12 ⇔x-2=3
⇔ x=6 ⇔x=5
(x+7)-25=13 450:(x-19)=50
⇔x+7=38 ⇔x-19=9
⇔x=31 ⇔x=28
Bài tập:
a) |2x + 1| - 19 = -7
b) -28 - 7 .|- 3x + 15| = -70
c) | 18 - 2.| -x + 5|| = 12
d) 12 - 2 .(-x + 3)2= -38
e) -20 + 3.(2x + 1) ^3 = -101
Ai giúp e vs!
a) /2x+1/-19=-7 /2x+1/=-7+-19 /2x+1/=-12 vì /2x+1/=12 chứ ko đc =-12 =>x ko xảy ra
a) x=5,5 và x=16,5
b) x=7 và x=3
c) x=-10 và x=8 và x=2 và x=20
d) x=8 và x =-2
e) x=-3,5
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
Giúp e vs ạ Giải bất pt: a) 2x - x(3x + 1) < 15 - 3x(x + 2) b) 4(x - 3)² - (2x - 1)² ≥ 12x
a: =>2x-3x^2-x<15-3x^2-6x
=>x<-6x+15
=>7x<15
=>x<15/7
b: =>4x^2-24x+36-4x^2+4x-1>=12x
=>-20x+35>=12x
=>-32x>=-35
=>x<=35/32
\(a,2x-x\left(3x+1\right)< 15-3x\left(x+2\right)\\ \Leftrightarrow2x-3x^2-x< 15-3x^2-6x\\ \Leftrightarrow3x^2-3x^2+2x+6x-x< 15\\ \Leftrightarrow7x< 15\\ \Leftrightarrow x< \dfrac{15}{7}\)
Vậy S={-∞; 15/7}
\(b,4\left(x-3\right)^2-\left(2x-1\right)^2\ge12x\\ \Leftrightarrow4\left(x^2-6x+9\right)-\left(4x^2-4x+1\right)-12x\ge0\\ \Leftrightarrow4x^2-4x^2-24x+4x-12x\ge-36+1\\ \Leftrightarrow-32x\ge-35\\ \Leftrightarrow x\le\dfrac{35}{32}\)
Vậy S={-∞; 35/32]
Tính giá trị biểu thức
a) 7/5 x 3/4 : 4/5 = ........................................
= ........................................
Tìm x:
b) x - 3/9 = 8/7
a) 21/20 : 4/5
= 21/16
b) x = 8/7+3/9
x = 31/21
tìm x:
17–14(x+1)=13–4(x+1)–5(x-3)
7(4x+3)-4(x-1)=15(X+0,75)+7
3x(x+1)−2x(x+2)=x mũ 2 – 1
Bạn nào giúp mik VS ;)
a) 17 - 14( x + 1 ) = 13 - 4( x + 1 ) - 5( x - 3 )
<=> 17 - 14x - 14 = 13 - 4x - 4 - 5x + 15
<=> 17 - 14 - 13 + 4 - 15 = -4x - 5x + 14x
<=> -21 = 5x
<=> x = -21/5
b) 7( 4x + 3 ) - 4( x - 1 ) = 15( x + 0, 75 ) + 7
<=> 28x + 21 - 4x + 4 = 15x + 45/4 + 7
<=> 28x - 4x - 15x = 45/4 + 7 - 21 - 4
<=> 9x = -27/4
<=> x = -3/4
c) 3x( x + 1 ) - 2x( x + 2 ) = x2 - 1
<=> 3x2 + 3x - 2x2 - 4x = x2 - 1
<=> 3x2 + 3x - 2x2 - 4x - x2 = -1
<=> -x = -1
<=> x = 1
a, \(17-14\left(x+1\right)=13-4\left(x+1\right)-5\left(x-3\right)\)
\(\Leftrightarrow17-14x-14=13-4x-4-5x+15\)
\(\Leftrightarrow3-14x=24-9x\Leftrightarrow3-14x-24+9x=0\)
\(\Leftrightarrow-21-5x=0\Leftrightarrow5x=-21\Leftrightarrow x=-\frac{21}{5}\)
b, \(7\left(4x+3\right)-4\left(x-1\right)=15\left(x+0,75\right)+7\)
\(\Leftrightarrow28x+21-4x+1=15x+\frac{45}{4}+7\)
\(\Leftrightarrow9x=-\frac{27}{4}\Leftrightarrow x=-\frac{3}{4}\)
c, \(3x\left(x+1\right)-2x\left(x+2\right)=x^2-1\)
\(\Leftrightarrow3x^2+3x-2x^2-4x=x^2-1\)
\(\Leftrightarrow x^2-x=x^2-1\Leftrightarrow x=1\)
Tìm số tự nhiên x biết:
(x+2)-2=0
(x+3)+1=7
(3x-4)+4=12
(5x+4)-1=13
(4x-8)-3=5
8-(2x-4)=2
7+(5x+2)=14
5-(3x-11)=1
Giúp e vs ạ(Vui lòng trình bày ạ)
\(\left(x+2\right)-2=0\)
\(\Rightarrow x+2-2=0\)
\(\Rightarrow x=0\)
\(\left(x+3\right)+1=7\)
\(\Rightarrow x+3+1=7\)
\(\Rightarrow x+4=7\)
\(\Rightarrow x=3\)
\(\left(3x-4\right)+4=12\)
\(\Rightarrow3x-4+4=12\)
\(\Rightarrow3x=12\)
\(\Rightarrow x=4\)
\(\left(5x+4\right)-1=13\)
\(\Rightarrow5x+4-1=13\)
\(\Rightarrow5x+3=13\)
\(\Rightarrow5x=10\)
\(\Rightarrow x=2\)
\(\left(4x-8\right)-3=5\)
\(\Rightarrow4x-8-3=5\)
\(\Rightarrow4x-11=5\)
\(\Rightarrow4x=16\)
\(\Rightarrow x=4\)
\(8-\left(2x+4\right)=2\)
\(\Rightarrow8-2x-4=2\)
\(\Rightarrow4-2x=2\)
\(\Rightarrow2x=2\)
\(\Rightarrow x=1\)
\(7+\left(5x+2\right)=14\)
\(\Rightarrow7+5x+2=14\)
\(\Rightarrow9+5x=14\)
\(\Rightarrow5x=5\)
\(\Rightarrow x=1\)
\(5-\left(3x-11\right)=1\)
\(\Rightarrow5-3x+11=1\)
\(\Rightarrow16-3x=1\)
\(\Rightarrow3x=15\)
\(\Rightarrow x=5\)
gấp m.n giải giúp e với, ai giúp với
tìm x biết
a, (2x-3)-(x-5)=(x+2)-(x+1)
b, 2(x-1)-5(x+2)=-10
c, 2(x-5)-3(x+7)=14
d, 5(x-6)-2(x+3)=12
e, -7(5-x)-2(x-10)=15
a, 2x-3-x+5=x+2-x+1
2x-x-x+x=2+1+3-5
0x=1
=> x thuộc rỗng (vì số nào nhân với 0 cũng bằng 0)
b, 2x-2-5x+10=-10
2x-5x=-10+2-10
-3x=2
x=-2/3
c, 2x-10-3x+21=14
2x-3x=14+10-21
-x=3
x=-3
d, 5x-6-2x+6=12
5x-2x=12+6-6
3x=12
x=4
e, -35+7x-2x+10=15
7x-2x=15+35-10
5x=40
x=8