a, X+5=2015-(12-7) c, (105-x):25=20150+1
b,-7|x+3|=-49 d,10-2x=25-3x
1/2×(2×x-3)+105/2=-137/2 A,-12×25-25×75-25×13 B,-50/7×49/10-35/2×-10/7+ -25/3× -9/5 C,-354+265-156+125 D,-74+40-50+16-35 E,-2/3×4/5+-4/5×4/3-0,125
1/2×(2×x-3)+105/2=-137/2
1/2×(2×x-3)=-137/2-105/2
1/2×(2×x-3)=-242/2
2×x-3=-242/2:1/2
2×x-3=-242
2.x=(-242)+3
2.x=239
x=239:2
x=239/2
A,-12×25-25×75-25×13
=[(-12)-75-13].25
=(-100).25
-2500
B,-50/7×49/10-35/2×-10/7+ -25/3× -9/5
=(-35)-(-25)+(-13)
=-23
C,-354+265-156+125
=[(-354)-156]+(265+125)
=(-510)+277
=-233
D,-74+40-50+16-35
=(-74)+40+(-50)+16+(-35)
=[(-74)+(-35)]+[40+(-50)+16]
=(-109)+26
=-83
E,-2/3×4/5+-4/5×4/3-0,125
=-2/3.4/5+4/5.(-4/3)-0,125
=4/5.[-2/3+(-4/3)]-0,125
=4/5.(-2)-0,125
=-8/5-0,125
=(-1,6)+(-0,125)
=-1,725
a, 2.x + 7 = 15
b, 25 – 3.(6 – x) = 22
c, [(2x – 11) : 3 + 1].5 = 20
d, (25 – 2x)3 : 5 – 32 = 42
e, 2 . 3x = 10 . 312 + 8 . 274
g, x – 12 = (–8) + (–17)
h, 7 – 2x = 18 – 3x
i, 3(x + 5) – x – 11 = 24
a, 2.x + 7 = 15
2x = 8
x = 4
b, 25 – 3.(6 – x) = 22
3.(6-x) = 3
6-x = 1
x = 5
c, [(2x – 11) : 3 + 1].5 = 20
(2x-11) : 3+1 = 4
(2x-11):3 = 3
2x-11 = 1
2x = 12
x = 6
e, 2 . 3x = 10 . 312 + 8 . 274
6x = 3120 + 2192
6x = 5312
x = 5312/6
g, x – 12 = (–8) + (–17)
x - 12 = -25
x = -13
Lần sau tách nhỏ nội dung câu hỏi ra nha em, chứ trả lời thế này biếng lắm '^^ Chị làm chỉ mang tính tham khảo kết quả thôi, còn cụ thể thì em tách từng bước một ra he :>
a, \(2\cdot x+7=15\)
\(\Leftrightarrow2\cdot x=8\)
\(\Leftrightarrow x=4\)
Vậy x = 4.
b, \(25-3\cdot\left(6-x\right)=22\)
\(\Leftrightarrow3\cdot\left(6-x\right)=3\)
\(\Leftrightarrow6-x=1\)
\(\Leftrightarrow x=5\)
Vậy x = 5.
c, \(\left[\left(2x-11\right):3+1\right]\cdot5=20\)
\(\Leftrightarrow\left(2x-11\right):3+1=4\)
\(\Leftrightarrow\left(2x-11\right):3=3\)
\(\Leftrightarrow2x-11=9\)
\(\Leftrightarrow2x=20\)
\(\Leftrightarrow x=10\)
Vậy x = 10.
d, \(\left(25-2x\right)\cdot3:5-32=42\)
\(\Leftrightarrow\)\(\frac{3\cdot\left(25-2x\right)}{5}=74\)
\(\Leftrightarrow3\cdot\left(25-2x\right)=370\)
\(\Leftrightarrow25-2x=\frac{370}{3}\)
\(\Leftrightarrow2x=-\frac{295}{3}\)
\(\Leftrightarrow x\approx49\)
Vậy \(x\approx49\) .
e, \(2\cdot3x=10\cdot312+8\cdot274\)
\(\Leftrightarrow6x=5312\)
\(\Leftrightarrow x=5312:6\approx885\)
Vậy \(x\approx885\) .
g, \(x-12=\left(-8\right)+\left(-17\right)\)
\(\Leftrightarrow x-12=-25\)
\(\Leftrightarrow x=-25+12=-13\)
Vậy x = -13.
h, \(7-2x=18-3x\)
\(\Leftrightarrow-2x+3x=18-7\)
\(\Leftrightarrow x=11\)
Vậy \(x=11\) .
i, \(3\cdot\left(x+5\right)-x-11=24\)
\(\Leftrightarrow3x+15-x-11=24\)
\(\Leftrightarrow2x=24+11-15\)
\(\Leftrightarrow2x=20\)
\(\Leftrightarrow x=10\)
Vậy \(x=10\) .
Thanks mn ^v^
Tim X
3) -12 + (2x – 9) + x= 0
4) 11 + (15 - x) = 1
5) 4 - (27 - 3) = x - (13 - 4)
6) 8 - (x - 10) = 23 - (- 4 +12)
7) 105 – 5(10 – 5x) = -20
8) (x -1)(8-2x)(3x+123) = 0
9) (x2 - 25)(x+ 10) = 0
10) x(x2+5) =
3) \(-12+2x-9+x=0\\ -21+3x=0\\ 3x=21\\ x=7\)
4)
\(11+\left(15-x\right)=1\)
\(15-x=1-11\)
\(15-x=-10\)
\(x=15-\left(-10\right)\)
\(x=25\)
5)
\(4-\left(27-3\right)=x-\left(13-4\right)\)
\(4-24=x-9\)
\(x-9=-20\)
\(x=-20+9\)
\(x=-11\)
\(3.-12+\left(2x-9\right)+x=0.\)
\(\Leftrightarrow-12+2x-9+x=0.\Leftrightarrow3x=21.\Leftrightarrow x=7.\)
Vậy \(x=7.\)
\(4.11+\left(15-x\right)=1.\Leftrightarrow11+15-x=1.\Leftrightarrow26-x=1.\Leftrightarrow x=25.\)
Vậy \(x=25.\)
\(5.4-\left(27-3\right)=x-\left(13-4\right).\Leftrightarrow4-24=x-9.\Leftrightarrow-20=x-9.\Leftrightarrow x=-11.\)
Vậy \(x=-11.\)
\(6.8-\left(x-10\right)=23-\left(-4+12\right).\Leftrightarrow8-x+10=23-8.\Leftrightarrow18-x=15.\Leftrightarrow x=3.\)
Vậy \(x=3.\)
\(7.105-5\left(10-5x\right)=-20.\Leftrightarrow105-50+25x=-20.\Leftrightarrow25x=-75.\Leftrightarrow x=-3.\)
Vậy \(x=-3.\)
\(8.\left(x-1\right)\left(8-2x\right)\left(3x+123\right)=0.\)
\(\Leftrightarrow\left[{}\begin{matrix}x-1=0.\\8-2x=0.\\3x+123=0.\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1.\\x=4.\\x=-41.\end{matrix}\right.\)
Vậy \(x\in\left\{1;4;-41\right\}.\)
\(9.\left(x^2-25\right)\left(x+10\right)=0.\)
\(\Leftrightarrow\left(x-5\right)\left(x+5\right)\left(x+10\right)=0.\)
\(\Leftrightarrow\left[{}\begin{matrix}x-5=0.\\x+5=0.\\x+10=0.\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=5.\\x=-5.\\x=-10.\end{matrix}\right.\)
Vậy \(x\in\left\{5;-5;-10\right\}.\)
\(10.x\left(x^2+5\right)=0.\Leftrightarrow x=0.\)
Bài 1: Tìm x [GIÚPPPPPPPPPPPPPPPPPPP]
1) 5 – (10 – x) = 7
2) - 32 - (x – 5) = 0
3) -12 + (2x – 9) + x= 0
4) 11 + (15 - x) = 1
5) 4 - (27 - 3) = x - (13 - 4)
6) 8 - (x - 10) = 23 - (- 4 +12)
7) 105 – 5(10 – 5x) = -20
8) (x -1)(8-2x)(3x+123) = 0
9) (x2 - 25)(x+ 10) = 0
10) x(x2+5) = 0
\(1\)) \(5-\left(10-x\right)=7\)
\(10-x=5-7\)
\(10-x=-2\)
\(x=10-\left(-2\right)\)
\(x=12\)
\(2\)) \(-32-\left(x-5\right)=0\)
\(x-5=-32-0\)
\(x-5=-32\)
\(x=-32+5\)
\(x=-27\)
1)10-x=5-7
x=10-(-2)
x=12
2)x+5=0+32
x=32-5
x=27
3) -12+2x-9+x=0
-12+(2x+x-9)=0
3x-9=0+12
3x=12+9
x=21:3
x=7
4) 15-x=1-11
x=15-(-10)
x=25
5) 4-(27+3)=x-9
4-30=x-9
-26+9=x
x=-17
b ) [( 6x - 39) : 7] .4 = 12 c) 4( 3x - 4 ) - 2 = 18 d ) ( 3x - 10 ) :10 = 50
e) x- 7 = - 57 f ) x - [ 42 + (-25) = - 8 g) ( 3x - 24 ) . 73 = 2 . 74
h) x + 5 = 20 - ( 12 -7) k) I x - 5 I = 7 - ( -3) i) I x - 5 I = I 7 I
2x+1 . 22009 = 220010 10 - 2x = 25 - 3x
nik lộn
2x+1. 22009 = 22010
10 - 2x = 25 - 3x
1. a. 4x-20=0
b. 2x+x+12=0
c. x-5=3-x
d. 7-3x=9-x
2.
a. 7+2x=22-3x
b. 8x-3=5x+12
c. x-12+4x=25+2x-1
d. x+2x+3x-19=3x+5
e. 7-(2x+4)=-(x+4)
f. (x-1)-(2x-1)=9-x
a. 2/3x-1/2=1/10
b. 39/7:x=13
c. (14/5x-50):2/3=51
d. (x+1/2)(2/3-2x)=0
e. 2/3x-1/2x=5/12
g. (x.44/7+3/7)11/5-3/7=-2
h. x.13/4+(-7/6)x-5/3=5/12
i.93/17:x+(-4/17):x+22/7:52/3=4/11
j. 17/2-|2x-3/4|=-7/4
k. (x+1/5)^2+17/25=26/25
l. -32/27-(3x-7/9)^3=-24/27
a) \(\dfrac{2}{3}x-\dfrac{1}{2}=\dfrac{1}{10}\)
\(\dfrac{2}{3}x=\dfrac{1}{10}+\dfrac{1}{2}=\dfrac{3}{5}\)
\(x=\dfrac{3}{5}:\dfrac{2}{3}=\dfrac{9}{10}\)
b) \(\dfrac{39}{7}:x=13\)
\(x=\dfrac{\dfrac{39}{7}}{13}=\dfrac{3}{7}\)
c) \(\left(\dfrac{14}{5}x-50\right):\dfrac{2}{3}=51\)
\(\dfrac{14}{5}x-50=51\cdot\dfrac{2}{3}=34\)
\(\dfrac{14}{5}x=34+50=84\)
\(x=\dfrac{84}{\dfrac{14}{5}}=30\)
d) \(\left(x+\dfrac{1}{2}\right)\left(\dfrac{2}{3}-2x\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{2}=0\\\dfrac{2}{3}-2x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)
e) \(\dfrac{2}{3}x-\dfrac{1}{2}x=\dfrac{5}{12}\)
\(\dfrac{1}{6}x=\dfrac{5}{12}\)
\(x=\dfrac{5}{12}:\dfrac{1}{6}=\dfrac{5}{2}\)
g) \(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\dfrac{11}{5}-\dfrac{3}{7}=-2\)
\(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\cdot\dfrac{11}{5}=-2+\dfrac{3}{7}=-\dfrac{11}{7}\)
\(x\cdot\dfrac{44}{7}+\dfrac{3}{7}=-\dfrac{11}{7}:\dfrac{11}{5}=-\dfrac{5}{7}\)
\(\dfrac{44}{7}x=-\dfrac{5}{7}-\dfrac{3}{7}=-\dfrac{8}{7}\)
\(x=-\dfrac{8}{7}:\dfrac{44}{7}=-\dfrac{2}{11}\)
h) \(\dfrac{13}{4}x+\left(-\dfrac{7}{6}\right)x-\dfrac{5}{3}=\dfrac{5}{12}\)
\(\dfrac{25}{12}x-\dfrac{5}{3}=\dfrac{5}{12}\)
\(\dfrac{25}{12}x=\dfrac{5}{12}+\dfrac{5}{3}=\dfrac{25}{12}\)
\(x=1\)
Mỏi tay woa bn làm nốt nha!!
5) 6x – 5 = 3 + 4x 6) x – (17 – x) = x – 7
7) 9 – 25 = (7 – x) – ( 25 + 7) 8) 10 – 2.(4 – 3x) = - 4
9) (-12)2
.x = 56 + 10. 13x 10) 2x2
– 1 = 49
a) x + 2x + 3x = 36
b)7x - 2x - x = 24
c) (x : 5 ) - 10 = 5
d) 7 . ( x + 3 ) = 49
e) ( x - 5 ) . 4 =32
g) 7x - 3 = 25
h) 17 - ( x : 3 ) = 10
a/ x + 2x + 3x = 36
=> 6x = 36
=> x = 6
Vậy ..
b/ 7x - 2x - x = 24
=> 4x = 24
=> x = 6
Vậy ...
c/ (x : 5) - 10 = 5
=> x : 5 = 15
=> x = 75
Vậy ...
d/ 7. (x+3) = 49
=> x + 3 = 7
=> x = 4
Vậy ....
e/ (x - 5) . 4 = 32
=> x - 5 = 8
=> x = 13
Vậy. ..
g/ 7x - 3 = 25
=> 7x = 28
=> x = 4
Vậy ...
h/ 17 - (x :3) = 10
=> x : 3 = 17 - 10
=>x : 3 = 7
=> x = 21
Vậy ..
a) x + 2x + 3x = 36
=> 6x = 36
=> x = 6
b)7x - 2x - x = 24
=> 4x = 24
=> x = 6
c) (x : 5 ) - 10 = 5
=> x : 5 = 15
=> x = 3
d) 7 . ( x + 3 ) = 49
=> x + 3 = 7
=> x = 4
e) ( x - 5 ) . 4 =32
=> x - 5 = 8
=> x = 3
g) 7x - 3 = 25
=> 7x = 28
=> x = 4
h) 17 - ( x : 3 ) = 10
=> x : 3 = 7
=> x = 21
a) x + 2x + 3x = 36
=> 6x = 36 => x = 36 : 6 = 6.
b) 7x - 2x -x = 24
=> 4x = 24 => x = 24 : 4 = 6.
c)(x : 5) - 10 = 5
=> x : 5 = 5 + 10 = 15
=> x = 15 x 5 = 75.
d) 7. (x + 3) = 49
=> x + 3 = 49 : 7 = 7
=> x = 7 - 3 = 4.
e)(x - 5) . 4 = 32
=> x - 5 = 32 : 4 = 8
=> x = 8 + 5 = 13.
g) 7x - 3 = 25
=> 7x = 25 + 3 = 28 => x = 28 : 7 = 4
h) 17 - ( x : 3 ) = 10
=> x : 3 = 17 - 10 = 7
=> x = 7.3 = 21