a) 5x + 60 = 120
b) 213 - ( x + 25) = 112
c) 5x - 25 = 100
a) ( 213 - x ) + 35 = 120
b) ( 2x + 50 ) - 68 = 530
c) ( 3500 - 5x ) + 25 = 2430
d) ( 9x + 12 ) : 3 = 12
Làm nhanh giúp mình nha ~!
a) ( 213 - x ) + 35 = 120
b) ( 2x + 50 ) - 68 = 530
c) ( 3500 - 5x ) + 25 = 2430
d) ( 9x + 12 ) : 3 = 12
Làm nhanh giúp mình nha ~!
a) ( 213 - x ) + 35 = 120
b) ( 2x + 50 ) - 68 = 530
c) ( 3500 - 5x ) + 25 = 2430
d) ( 9x + 12 ) : 3 = 12
Làm nhanh giúp mình nha ~!
a) ( 213 - x ) + 35 = 120
b) ( 2x + 50 ) - 68 = 530
c) ( 3500 - 5x ) + 25 = 2430
d) ( 9x + 12 ) : 3 = 12
Làm nhanh giúp mình với ạ
a: (x-25)-175=0
b: 485-(6.x + 60)=5
c: (x+ 100).4=800
d: 390:(5x-5)=39
Giúp mik với mik đag cần gấp
mik ko vt lại đề bài nha
a x-25=0+175 b 6x+60=485-5
x-25=175 6x+60=480
x=175+25 6x=480-60
x=200 6x=420 x=420:6 x=70
lm tương tự nha bn hok tốt
a) ( 213 - x ) + 35 = 120
b) ( 2x + 50 ) - 68 = 530
c) ( 3500 - 5x ) + 25 = 2430
d) ( 9x + 12 ) : 3 = 12
Làm nhanh giúp mình nha ~!
Tìm x, biết:
a) 120 - 20 : x = 110
b) 213 - ( x - 13 ) = 1442 : 14
c) 2550 : [ 120 - ( x - 5 ) ] = 25
a) 120 - 20 : x = 110
20:x= 120 - 110
20:x= 10
x= 20:10=2
b) 213 - ( x - 13 ) = 1442 : 14
213 - (x-13)=103
x-13= 213 - 103
x-13=110
x=110+13
x=123
c) 2550 : [ 120 - ( x - 5 ) ] = 25
120 - (x-5) = 2550:25
120 - (x-5)=102
x-5 = 120 - 102
x-5= 18
x=18+5
x=23
a,120-20:X=110
20:X=120-110
20:X=10
X=20:10
X=2
b, 213-[X-13]=1442:14
213-[x-13]=103
x-13=213-103
x-13=110
x=110+13
x=123
c,2550:[120-{x-5}]=25
120-{x-5}=2550:25
120-x-5=102
x-5=120-102
x-5=18
x=18+5
x=23
Tìm số nguyên x , biết
a) 117 - x = 28 - ( -7 )
b) x - ( - 38 - 2x ) = ( - 3 ) - 8 + 2x
c) 65 - ( - x + 15 ) - 5x = - ( -12 + 5x )
d) 3x - ( -12 + 7x - 21 ) = -3 - ( 5x + 2 )
e) -123 - ( - 2x - 23 ) = - ( 120 - x )
g) - 45 - ( - 25 - 5x ) = - ( - 16 + x )
a, 117 - \(x\) = 28 - (-7)
117 - \(x\) = 28 + 7
117 - \(x\) = 35
\(x\) = 117 - 35
\(x\) = 82
b, \(x\) - (-38 - 2\(x\)) = (-3) - 8 + 2\(x\)
\(x\) + 38 + 2\(x\) = - 11 + 2\(x\)
3\(x\) + 38 = - 11 + 2\(x\)
3\(x\) - 2\(x\) = - 11 - 38
\(x\) = - 49
Bài 1:
a. Tính:
1+22+23+....+29+210
b. Tìm x biết:
a] 60 - 3 . [x-1] = 23. 3
b] [3x - 2]3 = 2 . 25
c] 5x+1 - 5x = 500
d] x2 = x4
a) Đặt: \(A=1+2^2+2^3+...+2^{10}\)
\(\Rightarrow2A=2\left(1+2^2+2^3+...+2^9+2^{10}\right)\)
\(\Rightarrow2A=2+2^3+2^4+...+2^{10}+2^{11}\)
\(\Rightarrow2A-A=\left(2+2^3+2^4+...+2^{10}+2^{11}\right)-\left(1+2^2+2^3+...+2^{10}\right)\)
\(\Rightarrow A=\left(2^3-2^3\right)+\left(2^4-2^4\right)+...+\left(2-1\right)+\left(2^{11}-2^2\right)\)
\(\Rightarrow A=0+0+...+1+\left(2^{11}-2^2\right)\)
\(\Rightarrow A=1+2^{11}-2^2=1+2048-4=2045\)
Vậy: \(1+2^2+2^3+...+2^{10}=2045\)
b)
a] \(60-3\left(x-1\right)=2^3\cdot3\)
\(\Rightarrow60-3\left(x-1\right)=24\)
\(\Rightarrow3\left(x-1\right)=36\)
\(\Rightarrow x-1=12\)
\(\Rightarrow x=13\)
b] \(\left(3x-2\right)^3=2\cdot2^5\)
\(\Rightarrow\left(3x-2\right)^3=2^6\)
\(\Rightarrow\left(3x-2\right)^3=\left(2^2\right)^3\)
\(\Rightarrow3x-2=2^2\)
\(\Rightarrow3x=6\)
\(x=2\)
c] \(5^{x+1}-5^x=500\)
\(\Rightarrow5^x\left(5-1\right)=500\)
\(\Rightarrow5^x\cdot4=500\)
\(\Rightarrow5^x=125\)
\(\Rightarrow5^x=5^3\)
\(\Rightarrow x=3\)
d] \(x^2=x^4\)
\(\Rightarrow x=x^2\)
\(\Rightarrow x-x^2=0\)
\(\Rightarrow x\left(1-x\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\1-x=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x=1\end{matrix}\right.\)