tìm x , biết
a) 5/6 - x = -7 / 12 + 2/3
b) ( 2,4x - 36 ) : 1va5/7 = -1
c) 2 ( x - 1 ) - 3 ( 2x + 2 ) - 4 ( 2x + 3 ) = 16
d ) ( x - 2 ) . ( x + 3 ) > 0
tìm x biết:
a) (x-3)2-4=0
b) x2-2x=24
c) (x+4)2-(x+1)(x-1)=16
d) (2x+1)2-4(x-1)2=9
e) (x+3)2-(x-4)(x+8)=1
f) (2x-1)2+(x+3)2-5(x+7)(x-7)=0
g) 3(x+2)2+(2x-1)2-7(x+3)(x-3)=36
- Gửi lẻ câu hỏi ra nha bạn 2 3 câu 1 lần thôi .
a) (x-3)2-4=0
⇒ (x-3)2=4
⇒ hoặc x-3=2⇒x=5
hoặc x-3=-2⇒x=1
c) (x+4)2-(x+1)(x-1)=16
⇒ x2+8x+16-x2+1=16
⇒ 8x+17=16
⇒ 8x=-1
⇒ x=-1/8
Tìm số tự nhiên x,biết:
a)58 + 7x = 100
b) ( x –12):12=12
c) x -56 : 4= 16
d) 101 +(36 –4x) =105
e) 2(x-51) = 2.23+ 20
f) 10 -(x –3): 2 = 72–110
g) 2x –49 = 5.32h) [(8x -12) : 4].33= 36
i) 52x –3–2 . 52= 52. 3 k) (x3–7) : 4 = 5
a: 7x+58=100
nên 7x=42
hay x=6
c: x-56:x=16
nên x-14=16
hay x=30
c)x - 56 : 4 = 16
x - 56 = 16 : 4
x- 56 = 4
x =4 + 56
x = 60
d)101 + (36 - 4x) = 105
(36- 4x ) = 105 - 101
36 - 4x = 4
4x = 36 - 4
4x = 32
x = 32:4
x = 8
a) 58 + 7x = 100
7x = 100 - 58
7x = 42
x = 42 : 7
x = 6
b) (x - 12) : 12 = 12
x - 12 = 12 . 12
x - 12 = 144
x = 144 + 12
x = 156
a)-3/5.5/7+3/-5.3/7+3/5.-6/7
b)3/13:-11/-6+-3/13:11/-5-2/13
c)1/2.(x+2)+3/8=7/16
d)1/3x+2/5(x+1)=0
-1/3+5/2x=1/6:(-2/9)
a: \(=\dfrac{-3}{5}\cdot\dfrac{5}{7}+\dfrac{-3}{5}\cdot\dfrac{3}{7}+\dfrac{-3}{5}\cdot\dfrac{6}{7}\)
\(=\dfrac{-3}{5}\left(\dfrac{5}{7}+\dfrac{3}{7}+\dfrac{6}{7}\right)=\dfrac{-3}{5}\cdot2=-\dfrac{6}{5}\)
b: \(=\dfrac{3}{13}\cdot\dfrac{6}{11}+\dfrac{3}{13}\cdot\dfrac{5}{11}-\dfrac{2}{13}=\dfrac{3}{13}-\dfrac{2}{13}=\dfrac{1}{13}\)
c: =>1/2x+1+3/8=7/16
=>1/2x=-15/16
=>x=-15/8
d: =>5/2x-1/3=1/6*(-9)/2=-9/12=-3/4
=>5/2x=-3/4+1/3=-9/12+4/12=-5/12
=>x=-1/6
tìm x biết:
(3x-1) [- 1/2x+5]=0
1/4+1/3:(2x-1)=-5
[2x+3/5]2 - 9/25=0
-5(x+1/5)-1/2(x-2/3)=3/2x - 5 /6
[x+1/2]x [2/3-2x]=0
17/2-|2x-3/4|=-7/4
2/3x-1/2x =5/12
(x+1/5)2+17/25=26/25
[x.44/7+3/7].11/5-3/7=-2
3[3x-1/2]+1/9=0
tìm x biết:
(3x-1) [- 1/2x+5]=0
1/4+1/3:(2x-1)=-5
[2x+3/5]2 - 9/25=0
-5(x+1/5)-1/2(x-2/3)=3/2x - 5 /6
[x+1/2]x [2/3-2x]=0
17/2-|2x-3/4|=-7/4
2/3x-1/2x =5/12
(x+1/5)2+17/25=26/25
[x.44/7+3/7].11/5-3/7=-2
3[3x-1/2]+1/9=0
Toán lớp 6Tìm x
Trả lời Câu hỏi tương tự
Chưa có ai trả lời câu hỏi này,bạn hãy là người đâu tiên giúp nguyenvanhoang giải bài toán này !
Bài 4. Tìm x, biết:
a) (2x + 1)^2 - 4(x + 2)^2 = 9
b) (x + 3)^2 - (x - 4)( x + 8) = 1
c) 3(x + 2)^2 + (2x - 1)^2 - 7(x + 3)(x - 3) = 36
\(a,\left(2x+1\right)^2-4\left(x+2\right)^2=9\\ \Leftrightarrow4x^2+4x+1-4\left(x^2+4x+4\right)-9=0\\ \Leftrightarrow4x^2-4x^2+4x-16x+1-16-9=0\\ \Leftrightarrow-12x=24\\ \Leftrightarrow x=\dfrac{24}{-12}=-2\\ b,\left(x+3\right)^2-\left(x-4\right)\left(x+8\right)=1\\ \Leftrightarrow x^2+6x+9-\left(x^2+4x-32\right)=1\\ \Leftrightarrow x^2-x^2+6x-4x=1-9-32\\ \Leftrightarrow2x=-40\\ \Leftrightarrow x=-20\\ c,3\left(x+2\right)^2+\left(2x-1\right)^2-7\left(x+3\right)\left(x-3\right)=36\\ \Leftrightarrow3\left(x^2+4x+4\right)+\left(4x^2-4x+1\right)-7\left(x^2-9\right)=36\\ \Leftrightarrow3x^2+12x+12+4x^2-4x+1-7x^2+63=36\\ \Leftrightarrow3x^2+4x^2-7x^2+12x-4x=36-12-1-63\\ \Leftrightarrow8x=-40\\ \Leftrightarrow x=\dfrac{-40}{8}=-5\)
Tìm x
a.2x+(1+2+3+4+...+100) = 15150
b.(x+1)+(x+2)+(x+3)+(x+4)+(x+5)+(x+6)+(x+7)+(x+8)=36
c.0+0+4+6+8+...+2x=110
\(2x+\left(1+2+3+...+100\right)=15150\)
\(2x+\left[\left(1+100\right)+\left(2+99\right)+...+\left(50+51\right)\right]=15150\)
\(2x+\left[101+101+...+101\right]=15150\)CÓ 50 SỐ 101
\(2x+\left[101\times50\right]=15150\)
\(2x=15150:5050\)
\(2x=3\)
\(x=3:2\)
\(x=1.5\)
a, 2x + (1+2+3+4+...+100) = 15150
=> 2x + \(\frac{\left(1+100\right).\left[\left(100-1\right)+1\right]}{2}\)= 15150
=> 2x + \(\frac{101.100}{2}\)= 15150
=> 2x + 5050 = 15150
=> 2x = 15150 - 5050
=> 2x = 10100
=> x = 10100 : 2
=> x = 5050
Vậy x = 5050
b, .(x+1)+(x+2)+(x+3)+(x+4)+(x+5)+(x+6)+(x+7)+(x+8)=36
=> (x + x + x + x +x + x +x +x ) + (1 + 2 + 3 + 4 + 5 + 6 + 7 + 8) = 36
=> 8x + 36 = 36
=> 8x = 0
=> x = 0
Vậy x = 0
c, 0+0+4+6+8+...+2x=110
Sửa đề :0 + 2 + 4 + 6 + 8 + ... + 2x = 110 = 2 + 4 + 6 + 8 + ... + 2x = 110
SSH : \(\frac{\left(2\text{x}-2\right)}{2}+1=x-1+1=x\)
Tổng : \(\frac{\left(2\text{x}+2\right).x}{2}=110\Leftrightarrow\frac{2.\left(x+1\right).x}{2}=110\)
\(\Leftrightarrow\left(x+1\right)x=110\)
\(\Leftrightarrow\left(10+1\right).10=110\)
=> x = 10
Vậy x = 10
#)Giải :
a) 2x + ( 1 + 2 + 3 + 4 + ... + 100 ) = 15150
=> 2x + [ ( 100 + 1 ) x 100 : 2 ] = 15150
=> 2x + 5050 = 15150
=> 2x = 10100
=> x = 5050
b) ( x + 1 ) + ( x + 2 ) + ... + ( x + 8 ) + ( x + 9 ) = 36
=> ( x + x + x + ... + x ) + ( 1 + 2 + 3 + ... + 9 ) = 36
=> ( x + x + x + ... + x ) + 45 = 36
=> ( x + x + x + ... + x ) = -9
=> x = -1
c) Đề kiểu j v ? xem lại đi bạn ???
ai giúp mình giải bài này với được k mình đang cần gấp ( xin cảm ơn)
Bài 1:
a,√3x+4−√2x+1=√x+3
b, √2x−5+√x+2=√2x+1
c, √x+4−√1−x=√1−2x
d, √x+9=5−√2x+4
Bài 2:
a,√x+4√x+4=5x+2
b, √x2−2x+1+√x2+4x+4=4
c, √x+2√x−1+√x−2√x−1=2
d,√x−2+√2x−5+√x+2+3√2x−5=7√2
Bài 3:
a, x2−7x=6√x+5−30
(đăng cho các CTV thử việc ^-^)
Tìm x:
a, -5/6 - x = 7/12 + -1/3
b, (4,5 - 2x).(-1 4/7) = 11/14
c, (2/11 + 1/3).x = (1/7 - 1/8).56
`a)-5/6-x=7/12+[-1]/3`
`-5/6-x=1/4`
`x=-5/6-1/4`
`x=-13/12`
`b)(4,5-2x).(-1 4/7)=11/14`
`(4,5-2x).(-11/7)=11/14`
`4,5-2x=11/14:(-11/7)=-0,5`
`2x=4,5-(-0,5)=5`
`x=5:2=2,5`
`c)(2/11+1/3)x=(1/7-1/8).56`
`17/33 x=1/56 .56=1`
`x=33/17`
Tìm x biết :
a, 4.(18 - 5x) - 12.(3x - 7) = 15.(2x - 16) - 6(x + 14)
b, 5.(3x + 5) - 4.(2x - 3) = 5x + 3.(2x + 12) + 1
c, 2.(5x - 8) - 3.(4x - 5) = 4.(3x - 4) + 11
d, (3x + 2)(2x + 9) - (x + 2)(6x + 1) = (x + 1) - (x - 6)
e, (8x - 3)(3x + 2) - (4x + 7)(x + 4)= (2x + 1)(5x - 1) - 33
Noob ơi, bạn phải đưa vào máy tính ý solve cái là ra x luôn, chỉ tội là đợi hơi lâu
a, 4.(18 - 5x) - 12(3x - 7) = 15(2x - 16) - 6(x + 14)
=> 72 - 20x - 36x + 84 = 30x - 240 - 6x - 84
=> (72 + 84) + (-20x - 36x) = (30x - 6x) + (-240 - 84)
=> 156 - 56x = 24x - 324
=> 24x + 56x = 324 + 156
=> 80x = 480
=> x = 480 : 80 = 6
Vậy x = 6
b, 5(3x + 5) - 4(2x - 3) = 5x + 3(2x + 12) + 1
=> 15x + 25 - 8x + 12 = 5x + 6x + 36 + 1
=> (15x - 8x) + (25 + 12) = 11x + 37
=> 7x + 37 = 11x + 37
=> 11x - 7x = 0
=> x = 0