450 : [ 41 - ( 2x - 5 ) ] = 3 mũ 2 . 5
450 ː [41 - (2x -5)] = 3 mũ 2 x 5
450 : [ 41 - ( 2x - 5 )] = 32 . 5
450 : [ 41 - ( 2x - 5 )] = 9 . 5
450 : [ 41 - ( 2x - 5 )] = 45
41 - ( 2x - 5) = 450 : 45
41 - ( 2x - 5 ) = 10
2x - 5 = 41 - 10
2x - 5 = 31
2x = 31 + 5
2x = 36
x = 36 : 2
x = 18
Vậy x = 18
Học tốt!!!
\(450:\left[41-\left(2x-5\right)\right]3^{2.5}\)
450 : [41 - 2x + 5] = 9 . 5
450 : [46 - 2x] = 45
46 - 2x = 10
2x = 36
x = 18
210-5x=200
210-5(x-10)=200
450:[41-(2x-5)]= 3^2.5
210:x-10=20
(5x-39).7+3=80
(2x+1):7=2^2.3^2
lưu ý:^ là mũ
VD3^2=ba mũ hai
làm đầy đủ hộ mình nha
a)210-5x=200
5x=210-200
5x=10
x=10:2
x=5
B)210-5(x-10)=200
5(x-10)=210-200
5(x-10)=10
x-10=10:5=2
x=2+10=12
c)450:[41-(2x-5)]=3 mũ 2 .5
450:[41+5-2x]=45
41+5-2x=450:45
41+5-2x=10
2x=36
x=18
D)210:x-10=20
210:x=20+10
210:x=30
x=210:30
x=7
E)(5x-39).7+3=80
(5x-39).7=77
5x-39=11
5x=50
x=10
F(2x+1):7=2 mũ 2 nhân 3 mũ 2
(2x+1):7=36
2x+1=252
2x=251
x=251/2
a,210-5(x-11)=200
b,(2x+1):7=2^2+3^2
c,450:[41-(2x-5]=3^2.5
d,(5x-9).7+3=80
\(a,210-5\left(x-11\right)=200\\ \Rightarrow5\left(x-11\right)=10\\ \Rightarrow x-11=2\\ \Rightarrow x=13.\\ b,\left(2x+1\right):7=2^2+3^2\\ \Rightarrow\left(2x+1\right):7=4+9\\ \Rightarrow\left(2x+1\right):7=13\\ \Rightarrow2x+1=91\\ \Rightarrow2x=90\\ \Rightarrow x=45.\\ c,450:\left[41-\left(2x-5\right)\right]=3^2.5\\ \Rightarrow450:\left[41-\left(2x-5\right)\right]=45\\ \Rightarrow41-\left(2x-5\right)=10\\ \Rightarrow2x-5=31\\ \Rightarrow2x=36\\ \Rightarrow x=18.\\ d,\left(5x-9\right).7+3=80\\ \Rightarrow\left(5x-9\right).7=77\\ \Rightarrow5x-9=11\\ \Rightarrow5x=20\\ \Rightarrow x=4.\)
a) \(210-5\left(x-11\right)=200\)
\(5.\left(x-11\right)=210-200\)
\(5.\left(x-11\right)=10\)
\(x-11=10:5\)
\(x-11=2\)
\(x=2+11\)
\(x=13\)
b) \(\left(2x+1\right):7=2^2+3^2\)
\(\left(2x+1\right):7=13\)
\(2x+1=13.7\)
\(2x=91-1\)
\(2x=90\)
\(x=90:2\)
\(x=45\)
c) \(450:\left[41-\left(2x-5\right)\right]=3^2.5\)
\(450:\left[41-\left(2x-5\right)\right]=45\)
\(\left[41-\left(2x-5\right)\right]=450:45\)
\(\left[41-\left(2x-5\right)\right]=10\)
\(2x-5=41-10\)
\(2x-5=31\)
\(2x=31+5\)
\(2x=36\)
\(x=36:2\)
\(x=18\)
d) \(\left(5x-9\right).7+3=80\)
\(\left(5x-9\right).7=80-3\)
\(5x-9=77:7\)
\(5x-9=11\)
\(5x=11+9\)
\(5x=20\)
\(x=20:5\)
\(x=4\)
2 mũ 2 + 4.2 mũ n = 5.2 mũ n
9 < 3 mũ n < 234
5 < 5 mũ n < 625
720 : [ 41 - ( 2x - 5 ) ] = 2 mũ 3. 5
a)450:[41-(2x+5)]=3^2.5
\(450:\left[41-\left(2x+5\right)\right]=3^2.5\)
\(\Leftrightarrow41-2x-5=12,5\)
\(\Leftrightarrow-2x=-23,5\)
\(\Leftrightarrow x=\dfrac{47}{4}\)
`450 : [41 - (2x+5)] = 3^2 .5`
`=> 450 : (41 - 2x-5) = 9.5`
`=> 450 : (36 - 2x) = 45`
`=> 36-2x= 450:45`
`=>36-2x=10`
`=> 2x= 26`
`=> x= 13`
Vậy `x= 13`
600 : [ 450 : {450 -(4.5 mũ 3 - 2 mũ 3 . 5 mũ 2 )}]
312 + (146 -X ) =401
11- (15 + 21 ) + X- (25-9)
2- X +177 - (-5)
X -12 = (-9) - 15
Tìm số tự nhiên x , biết:
a, 36:(x–5) = 2 2
b, [3.(70–x)+5]:2 = 46
c, 450:[41–(2x–5)] = 3 2 .5
d, 230+[ 2 4 +(x–5)] = 315. 2018 0
e, 2 x + 2 x + 1 = 48
f, 3 x + 2 + 3 x = 2430
a, 36:(x–5) = 2 2
(x–5) = 9
x = 14
b, [3.(70–x)+5]:2 = 46
[3.(70–x)+5] = 92
70–x = 29
x = 41
c, 450:[41–(2x–5)] = 3 2 .5
41–(2x–5) = 10
2x–5 = 31
2x = 36
x = 18
d, 230+[ 2 4 +(x–5)] = 315. 2018 0
16+(x–5) = 315–230
x–5 = 85–16
x = 69+5
x = 74
e, 2 x + 2 x + 1 = 48
2 x .(2+1) = 48
2 x = 16 = 2 4
x = 4
f, 3 x + 2 + 3 x = 2430
3 x . 3 2 + 1 = 2430
3 x = 2430:10 = 243 = 3 5
x = 5
bài 1: tìm x thuộc Z
m) (1900-2x):35 - 32 = 16
n) 720:[41 - (2x - 5)] = 2 mũ 3 . 5
o) (x-5).(x mũ 2 - 4) = 0
m , Ta có : \(\left(1900-2.x\right):3-32=16\)
\(\Leftrightarrow\frac{1900-2.x}{35}-32=16\)( Nhân hai vế với 35 )
\(\Leftrightarrow1900-2.x-1120=560\)
\(\Leftrightarrow780-2.x=560\)
\(\Leftrightarrow-2.x=560-780\)
\(\Leftrightarrow\) \(-2.x=-220\)
\(\Rightarrow x=110\)
Vậy x = 110
n, Ta có : \(720:\left[41-\left(2.x-5\right)\right]=2^3.5\)
\(\Leftrightarrow720:\left(41-2.x+5\right)=8.5\)
\(\Leftrightarrow720:\left(46-2.x\right)=40\)
\(\Leftrightarrow\frac{720}{46-2.x}=40\)
\(\Leftrightarrow\frac{720}{2.\left(23-x\right)}=40\)
\(\Leftrightarrow\frac{360}{23-x}\)
\(\Leftrightarrow360=40.\left(23-x\right)\)
\(\Leftrightarrow9=23-x\)
\(\Leftrightarrow x=14\)
Vậy x = 14
o, Ta có : \(\left(x-5\right).\left(x^2-4\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x-5=0\\x^2-4=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=5\\x=\pm2\end{cases}}\)
Vậy \(x=5;-2;2\)