Bài 2.Tìm x
a,10+2x=4^5:4^3
b,14x+54=82
c,15x-133=17
K
Khách
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Những câu hỏi liên quan
16 tháng 7 2023
A, 7[x + 5] - 20 = 190
7x + 35 - 20 = 190
7x + 15 = 190
7x = 175
x = 25
B, 155 - 10[x + 1] = 55
155 - 10x - 10 = 55
-10x + 90 = 55
-10x = -35
x = 3.5
C, 6[x + 2^3] + 40 = 100
6[x + 8] + 40 = 100
6x + 48 + 40 = 100
6x + 88 = 100
6x = 1
2 x = 2
D, 15x - 133 = 17
15x = 150
x = 10
E, 90[x + 2] = 45
90x + 180 = 45
90x = -135
x = -1.5
F, 4x + 54 = 82
4x = 28
x = 7
G, 17x - 20 = 14
17x = 34
x = 2
KQ
5
15 tháng 8 2018
a. 95 - 5.(x + 2) = 45
5.(x + 2) = 95 - 45
x + 2 = 50 : 5
x = 10 - 2
x = 8
b. 14x + 54 = 82
14x = 82 - 54
x = 28 : 14
x = 2
c. 15x - 133 = 17
15x = 17 + 133
x = 150 : 15
x = 10
d. 155 - 10.(x + 1) = 55
10.(x + 1) = 155 - 55
x + 1 = 100 : 10
x = 10 - 1
x = 9
8 tháng 9 2019
1) 70 - 5( x - 3 ) = 45
5( x - 3 ) = 70 - 45
5( x - 3 ) = 25
x - 3 = 25 : 5
x - 3 = 5
x = 5 + 3
x = 8
2) 12 + ( 5 + x ) = 20
5 + x = 20 - 12
5 + x = 8
x = 8 - 5
x = 3
3) 130 - ( 100 + x ) = 25
100 + x = 130 - 25
100 + x = 105
x = 105 - 100
x = 5
4) 175 + ( 30 - x ) = 200
30 - x = 200 - 175
30 - x = 25
x = 30 - 25
x = 5
8 tháng 9 2019
5) 5( x + 12 ) + 22 = 92
5( x + 12 ) = 92 - 22
5( x + 12 ) = 70
x + 12 = 70 : 5
x + 12 = 14
x = 14 - 12
x = 2
6) 95 - 5( x + 2 ) = 45
5( x + 2 ) = 95 - 45
5( x + 2 ) = 50
x + 2 = 50 : 5
x + 2 = 10
x = 10 - 2
x = 8
7) 14x + 54 = 82
14x = 82 - 54
14x = 28
x = 28 : 14
x = 2
8) 15x - 133 = 17
15x = 17 + 133
15x = 150
x = 150 : 15
x = 10
9) 155 - 10( x + 1 ) = 55
10( x + 1 ) = 155 - 55
10( x + 1 ) = 100
x + 1 = 100 : 10
x + 1 = 10
x = 10 - 1
x = 9
6 tháng 11 2021
a) \(\Rightarrow x^2+4x+25-x^2=3\Rightarrow4x=-22\Rightarrow x=-\dfrac{11}{2}\)
b) \(\Rightarrow\left(4x+3-2x+3\right)\left(4x+3+2x-3\right)=0\)
\(\Rightarrow2\left(x+3\right).6x=0\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x=-3\end{matrix}\right.\)
TP
1
30 tháng 10 2023
a: ĐKXD: x<>0
\(\dfrac{14x^3+12x^2-14x}{2x}=\left(x+2\right)\left(3x-4\right)\)
=>\(\dfrac{2x\left(7x^2+6x-7\right)}{2x}=\left(x+2\right)\left(3x-4\right)\)
=>\(7x^2+6x-7=3x^2-4x+6x-8\)
=>\(7x^2+6x-7=3x^2+2x-8\)
=>\(4x^2+4x+1=0\)
=>\(\left(2x+1\right)^2=0\)
=>2x+1=0
=>x=-1/2(nhận)
b: \(\left(4x-5\right)\left(6x+1\right)-\left(8x+3\right)\left(3x-4\right)=15\)
=>\(24x^2+4x-30x-5-\left(24x^2-32x+9x-12\right)=15\)
=>\(24x^2-26x-5-24x^2+23x+12=15\)
=>-3x+7=15
=>-3x=8
=>\(x=-\dfrac{8}{3}\)
7 tháng 7 2017
\(2^2.\left(x+3^2\right)-5=55\)
\(4.\left(x+9\right)-5=55\)
\(4.\left(x+9\right)=55+5\)
\(4.\left(x+9\right)=100\)
\(x+9=100:4\)\(\)
\(x+9=25\)
\(x=25-9\)
\(x=16\)
\(7.\left(x+5^2\right)-20=190\)
\(7.\left(x+25\right)-20=190\)
\(7.\left(x+25\right)=190+20\)
\(7.\left(x+25\right)=210\)
\(x+25=210:7\)
\(x+25=30\)
\(x=30-25\)
\(x=5\)
\(6.\left(x+2^3\right)+40=100\)
\(6.\left(x+8\right)+40=100\)
\(6.\left(x+8\right)=100-40\)
\(6.\left(x+8\right)=60\)
\(x+8=60:6\)
\(x+8=10\)
\(x=10-8\)
\(x=2\)
\(95-5.\left(x+2\right)=45\)
\(5.\left(x+2\right)=95-45\)
\(5.\left(x+2\right)=50\)
\(x+2=50:5\)
\(x+2=10\)
\(x=10-2\)
\(x=8\)
\(15.x-133=17\)
\(15.x=17+133\)
\(15.x=150\)
\(x=150:15\)
\(x=10\)
\(14.x+54=82\)
\(14.x=82-54\)
\(14.x=28\)
\(x=28:14\)
\(x=2\)
7 tháng 7 2017
1/ 2/ 3/ 4/
22(x + 32) - 5 = 55 7(x + 52) - 20 = 190 6(x + 23) + 40 = 100 95 - 5(x + 2) = 45
4(x + 9) - 5 = 55 7(x + 25) - 20 = 190 6(x + 6) + 40 = 100 5(x + 2) = 95 - 45
4(x + 9) = 55 + 5 7(x + 25) = 190 + 20 6(x + 6) = 100 - 40 5(x + 2) = 50
4(x + 9) = 60 7(x + 25) = 210 6(x + 6) = 60 x + 2 = 50 : 5
x + 9 = 60 : 4 x + 25 = 210 : 7 x + 6 = 60 : 6 x + 2 = 10
x + 9 = 15 x + 25 = 30 x + 6 = 10 x = 10 - 2
x = 15 - 9 x = 30 - 25 x = 10 - 6 x = 8
x = 6 x = 5 x = 4
5/ 6/
15x - 133 = 17 14x + 54 = 82
15x = 17 + 133 14x = 82 - 54
15x = 150 14x = 28
x = 150 : 15 x = 28 : 14
x = 10 x = 2
MV
2 tháng 7 2017
a)
\(512-\left(128-5x\right)=3x+12\\ 512-128+5x=3x+12\\ 384+5x=3x+12\\ 5x-3x=12-384\\ 2x=-372\\ x=\left(-372\right):2\\ x=-186\)
b)
\(\left(2x-1\right)+\left(4x-2\right)+...+\left(400x-200\right)=5+10+...+1000\\ \left(2x+4x+...+400x\right)-\left(1+2+...+200\right)=5+10+...+1000\\ x\left(2+4+...+400\right)=\left(5+10+...+1000\right)+\left(1+2+...+200\right)\\ 2x\cdot\left(1+2+...+200\right)=5\cdot\left(1+2+...+200\right)+1\cdot\left(1+2+...+200\right)\\ 2x\cdot\left(1+2+...+200\right)=\left(5+1\right)\cdot\left(1+2+...+200\right)\\ 2x\cdot\left(1+2+...+200\right)=6\cdot\left(1+2+...+200\right)\\ \Rightarrow2x=6\\ x=6:2\\ x=3\)
c)
\(\left(x+2\right)+\left(4x+4\right)+\left(7x+6\right)+...+\left(25x+18\right)+\left(28x+20\right)=1560\\ \left(x+4x+7x+...+25x+28x\right)+\left(2+4+6+...+18+20\right)=1560\\ x\left(1+4+7+...+25+28\right)+110=1560\\ 145x+110=1560\\ 145x=1560-110\\ 145x=1450\\ x=1450:145\\ x=10\)
d)
\(x+4x+5x+9x+14x+...+97x=500\\ x\left(1+4+5+9+14+...+97\right)=500\)
Dãy số trong ngoặc có quy luật: Số thứ \(n\) bằng số thứ \(n-1\) cộng số thứ \(n-2\)
Suy ra dãy số đó là: \(1+4+5+9+14+23+37+60+97=250\)
Thế vào ta được:
\(250x=500\\ x=500:250\\ x=2\)
e)
\(720-\left[41-\left(2x-5\right)\right]=2^3\cdot5\\ 720-41+\left(2x-5\right)=8\cdot5\\ 720-41+2x-5=40\\ \left(720-41-5\right)+2x=40\\ 674+2x=40\\ 2x=40-674\\ 2x=-634\\ x=\left(-634\right):2\\ x=-317\)
f)
\(697:\dfrac{15x+364}{x}=17\\ \dfrac{15x+364}{x}=697:17\\ \dfrac{15x+364}{x}=41\\ \dfrac{15x+364}{x}\cdot x=41x\\ 15x+364=41x\\ 364=41x-15x\\ 364=26x\\ x=364:26\\ x=14\)
17 tháng 10 2021
\(a,\Leftrightarrow x^2+2x+1-x^2+3x-2x=3\\ \Leftrightarrow3x=2\Leftrightarrow x=\dfrac{3}{2}\\ b,\Leftrightarrow x^2-x-6-x^2+6x-9=15\\ \Leftrightarrow5x=30\Leftrightarrow x=6\\ c,\Leftrightarrow x^3+3x^2+3x+1-x^3-3x^2-2x+3=0\\ \Leftrightarrow x=-4\)
17 tháng 10 2021
a) \(\left(x+1\right)^2-x\left(x-3\right)=2x+3\Rightarrow x^2+2x+1-x^2+3x=2x+3\)
\(\Rightarrow3x=2\Rightarrow x=\dfrac{2}{3}\)
HT
0
a) \(10+2x=4^5:4^3\)
\(\Leftrightarrow10+2x=4^2\)
\(\Leftrightarrow2x=6\)
\(\Leftrightarrow x=3\)
b) \(14x+54=82\)
\(\Leftrightarrow14x=28\)
\(\Leftrightarrow x=2\)
c) \(15x-133=17\)
\(\Leftrightarrow15x=150\)
\(\Leftrightarrow x=10\)
a) 10 + 2x = 4^5 : 4^3
=> 10 + 2x = 4^2
=> 2x = 6
=> x = 3
b) 14x + 54 = 82
=> 14x = 28
=> x = 2
c) 15x - 133 = 17
=> 15x = 150
=> x = 10
Mỗi câu bạn tính xong x bạn thêm chữ vậy x =... vào nha