Giúp me nhoa :3333
B1:
-5/7 . 2/11+-5/7.9/11+1 5/7
B2:
a)2x-2/7=5+2x/8
b)(40%.x-1,125):2 2/3 =-5/9
c)(2,8.x-32):40%=9/5
d)(3/2.x-1/2)^2=16/25
e)2/3.x+4/5.x+-3/5-50%
f)65-4^x+2=2020^0
Giải giúp với ạ,mình cảm ơn !
c)(2,8.x-32):40%=9/5
d)(3/2.x-1/2)^2=16/25
e)2/3.x+4/5.x+-3/5-50%
f)65-4^x+2=2020^0 giúp vs ạ
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!!
Bài 1:
a)-2x-3.( x-17 )= 34-2.( -x+25 )
b)17x+3.( -16x-37 )= 2x+43-4x
c){-3x+2. [ 45-x-3 ( 3x+7 ) -2x]+4x} = 55
g)-103-57: [ 5.( 2x-1 )2-( -9 )0 ]
Bài 2:
a)-5.( -x+7 )-3.( -x-5 )=-4.( 12-x )+48
b)7.( -x-7 )-4.( -2x-11 )=7.( 4x+10 )+9
c)-2.( 15-3x )-4.( -7x+8 )=-5-9.( -2x+1 )
d)5.( -3x-7 )-4.( -2x-11 )=7.( 4x+10 )+9
e)4( x-2 )2-13=( -3 )2.2-11.( -3 )
f)-52-( 2x-1 )3=( -13 ).( -3 )
Thực hiện phép tính:
A) 7/38 x 9/11 +7/38 x 4/11 -7/38 x 2/11
B) 5/31 x 21/25 + 5/31 x -7/10 - 5/31 x 9/20
C) ( -2/3 + 3/7 ) : 4/5 + (-1/3 + 4/7 ) : 4/5
D) 5/9 : ( 1/11 -5/22 ) + 5/9 : ( 1/15 - 2/3 )
E) 3/14 : 1/28 -13/21 : 1/28 + 29/42 : 1/28 - 8
F) ( -40/51 x 0,32 x17/20) : 64/75
Đây là dấu x ( là nhân ) mọi người nhé
mong mn giúp em ạ
A) 7/38 x 9/11 +7/38 x 4/11 -7/38 x 2/11
=7/38.(9/11+4/11-2/11)
=7/38
B) 5/31 x 21/25 + 5/31 x -7/10 - 5/31 x 9/20
=5/31.(21/25-7/10-9/20)
=5/31.(-31/100)
=-1/20
Bài 1:
a.35 1/6:(-4)/5-46 1/6:(-4)/5
b.1/6+5/6.3/2-3/2+1
c.-1/12-(2 5/8-1/3)
d.-5/4.8/9+-7/16.8/9-2
e.1/6.(-2 3/5)+1 2/5.(-13/5)
Bài 2
a.-5/8+x=(-2/3)^2
b.-1/4-3/4:x=-11/36
c.-22/15x+1/3=/-2/3-1/5/
d./-1/2-x/=1/3
e./2x+3/4/-6=-5
f.-5/7-/1/2-x/=-11/4
g.//x+5/-4/=3
h./17x-5/=/17x+5/
i./x-1/=2x-5
k.(x-1)^3=27
l.(2x-1)^2=25
n.5^x+2=625
m.(2x-1)^3=-8
o.x^2+x=0
Bài 1 tìm x
l) (x + 9) . (x2 – 25) = 0
e) |x - 4 |< 7
f) 40 < 31 + |x |< 47
g) | x + 3| ≤ 2
m) (-5x + 20).(x3 – 8) = 0
a) (x + 1).(y - 2) = 5
b) (x - 5).(y + 4) = -7
c) (x + 1)2 + (y – 1)2 = 0
d) (2x – 18)2 + ( y + 37)2 = 0
k |x-40|+|x-y+10|_<0
l) (x + 9) . (x2 – 25) = 0
<=> (x + 9) . (x – 5) . (x + 5) = 0
<=> \(\left[{}\begin{matrix}\text{x + 9 = 0}\\x-5=0\\x+5=0\end{matrix}\right.\left[{}\begin{matrix}x=-9\\x=5\\x=-5\end{matrix}\right.\)
Vậy S = \(\left\{-9,5,-5\right\}\)
e) |x - 4 |< 7
<=> \(\left[{}\begin{matrix}x-4=7\\x-4=-7\end{matrix}\right.< =>\left[{}\begin{matrix}x=11\\x=-3\end{matrix}\right.\)
Vậy S = \(\left\{11;-3\right\}\)
I,(x+9).(x^2-25)=0
tương đương:x+9=0
x^2-25=0
tương đương : x=-9
x=5
e,\(\left|x-4\right|\)=7
tương đương x-4=4
x-4=-4
tương đương :x=0
x=-8
Bài 1:
l) Ta có: \(\left(x+9\right)\left(x^2-25\right)=0\)
\(\Leftrightarrow\left(x+9\right)\left(x-5\right)\left(x+5\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x+9=0\\x-5=0\\x+5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-9\\x=5\\x=-5\end{matrix}\right.\)
Vậy: \(x\in\left\{-9;5;-5\right\}\)
e) Ta có: |x-4|<7
mà \(\left|x-4\right|\ge0\forall x\)
nên \(\left|x-4\right|\in\left\{0;1;2;3;4;5;6\right\}\)
\(\Leftrightarrow x-4\in\left\{0;1;-1;2;-2;3;-3;4;-4;5;-5;6;-6\right\}\)
hay \(x\in\left\{4;5;3;6;2;7;1;8;0;9;-1;10;-2\right\}\)
Vậy: \(x\in\left\{4;5;3;6;2;7;1;8;0;9;-1;10;-2\right\}\)
f) Ta có: \(40< 31+\left|x\right|< 47\)
\(\Leftrightarrow\left|x\right|+31\in\left\{41;42;43;44;45;46\right\}\)
\(\Leftrightarrow\left|x\right|\in\left\{10;11;12;13;14;15\right\}\)
hay \(x\in\left\{10;-10;11;-11;12;-12;13;-13;-14;14;15;-15\right\}\)
Vậy: \(x\in\left\{10;-10;11;-11;12;-12;13;-13;-14;14;15;-15\right\}\)
g) Ta có: \(\left|x+3\right|\le2\)
\(\Leftrightarrow\left|x+3\right|\in\left\{0;1;2\right\}\)
\(\Leftrightarrow x+3\in\left\{0;1;-1;2;-2\right\}\)
hay \(x\in\left\{-3;-2;-4;-1;-5\right\}\)
Vậy: \(x\in\left\{-3;-2;-4;-1;-5\right\}\)
Tìm x biet:
a,5/2x+x=32/15
b,x-7/2x=-32/15
c,-7/3x-7/4x+11/3=18/5
d,-5/6-3x=2/3
e,2x-5/9=-2/3
f,1/2-2/3x=7/12
g,7-|2x-3|=4
h,(19x+2.5^2):14=(13-8)^2-4^2
i,3/4x-2/3=2/7.1/6+5/7.1/6
k,(x+1/2).(2/3-2x)=0
l,x/2013-1/10-1/15-1/21-........-1/120=5/8
Bài 1. Tìm x, biết
b) -2x + 36 = 6
a) -5.x + 32 = (-2)3
d) êx - 4 ê< 7
f) 40 < 31 + êx ê< 47
g) | x + 3| ≤ 2
e) (x + 9) . (x2 – 25) = 0
h) (x – 5)2 = 9
Bài 1:
a) Ta có: \(-5x+32=\left(-2\right)^3\)
\(\Leftrightarrow-5x+32=-8\)
\(\Leftrightarrow-5x=-40\)
hay x=8
Vậy: x=8
b) Ta có: \(-2x+36=6\)
\(\Leftrightarrow-2x=6-36=-30\)
hay x=15
Vậy: x=15
e) Ta có: \(\left(x+9\right)\left(x^2-25\right)=0\)
\(\Leftrightarrow\left(x+9\right)\left(x-5\right)\left(x+5\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x+9=0\\x-5=0\\x+5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-9\\x=5\\x=-5\end{matrix}\right.\)
Vậy: \(x\in\left\{-9;5;-5\right\}\)
b,-2x+36=6
tương đương -2x=-30
tương đương x=15
a, -5x+32=(-2)^3
tương đương -5x+32=8
tương đương -5x=-24
tương đương x=24/5
Bài 1. Tính giá trị các lũy thừa sau: c) 53 d) 20200 e) 43 f) 12020 Bài 2. Viết kết quả các phép tính sau dưới dạng một lũy thừa: a) b) c) d) 18 12 3 :3 e) 15 15 4 .5 f) 3 3 16 :8 g) 8 4 4 .8 h) 3 2 3 .9 i) 5 2 27 . 3 . k) 4 4 12 12 24 :3 32 :16 m) 12 11 5 .7 5 .10 n) 10 10 2 .43 2 .85 Bài 3. Tính giá trị của biểu thức: 2 A 150 30: 6 2 .5; 2 B 150 30 : 6 2 .5; 2 C 150 30: 6 2 .5; 2 D 150 30 : 6 2 .5. Bài 4. Tìm số tự nhiên x biết: a) (x-6)2 = 9 b) (x-2)2 =25 3 c) 2x - 2 = 8 d) ( e) ( f) 2 (x 1) 4 g) ( h) ( i) ( k) ( m) ( n) ( Bài 5. Tìm số tự nhiên x biết: a) 2x = 32 b) 2 .4 128 x c) 2x – 15 = 17 d) 5x+1=125 e) 3.5x – 8 = 367 f) 3.2 18 30 x g) 5 2x+3 -2.52 =52 .3 h) 2.3x = 10. 312+ 8.274 i) 5x-2 - 3 2 = 24 - (68 : 66 - 6 2 ) k) m) n) Bài 6. Tính giá trị của các biểu thức sau: a) 9 12 . 19 – 3 24 . 19 b) 165 . 23 – 2 18 .5 – 8 6 . 7 c) 212. 11 – 8 4 . 6 – 163 .5 d)12 . 52 + 15 . 62 + 33 .2 .5 e) 34 . 15 + 45. 70 + 33 . 5 Bài 7. Thu gọn các biểu thức sau: a) A= 1+2+22 +23 +24 +....+299+2100 b) B= 5+53 +55 +...+597+599