a,123-5(x+4)=38
b,(3.x-2^4).7^3=2.7^4
a) 5(x+35)=515
b) 12x-33=3².3³
c) 6.x-5=19
d) 4.(x-12)+9=17
e) 123-5.(x+4)=38
f) (3x-2⁴).7³=2.7⁴
`@` `\text {Ans}`
`\downarrow`
`a)`
`5(x + 35) = 515`
`=> x + 35 = 515 \div 5`
`=> x+ 35 = 103`
`=> x = 103 - 35`
`=> x = 68`
Vậy, `x = 68`
`b)`
`12x - 33 = 3^2 * 3^3`
`=> 12x - 33 = 3^5`
`=> 12x = 3^5 + 33`
`=> 12x = 276`
`=> x = 276 \div 12`
`=> x = 23`
Vậy, `x = 23`
`c)`
`6x - 5 = 19`
`=> 6x = 19 + 5`
`=> 6x = 24`
`=> x = 24 \div 6`
`=> x = 4`
Vậy, `x = 4`
`d)`
`4(x - 12) + 9 = 17`
`=> 4(x - 12) = 17 - 9`
`=> 4(x - 12) = 8`
`=> x - 12 = 8 \div 4`
`=> x - 12 = 2`
`=> x = 14`
Vậy, `x = 14`
`e)`
123 - 5(x + 4) = 38`
`=> 5(x + 4)= 123 - 38`
`=> 5(x + 4) =85`
`=> x + 4 = 85 \div 5`
`=> x + 4 = 17`
`=> x = 13`
Vậy, `x = 13`
`f)`
`(3x - 2^4) * 7^3 = 2 * 7^4`
`=> 3x - 2^4 = 2 * 7^4 \div 7^3`
`=> 3x - 2^4 = 2* 7`
`=> 3x - 2^4 = 14`
`=> 3x = 14 + 2^4`
`=> 3x = 30`
`=> x = 30 \div 3`
`=> x = 10`
Vậy, `x = 10.`
Bài 2. Tìm x biết:
a, 128 - 3(x + 4) = 23 d, 720 : [41 - (2x - 5)] = 2 3 .5
b, [(4x + 28).3 + 55] : 5 = 35 e, 123 – 5.( x + 4 ) = 38
c, (12x - 4 3 ).8 3 = 4.8 4 g, ( 3x – 2 4 ) .7 3 = 2.7 4
a,
128-3x-12=23
3x=128-12-23
3x=93
x=93:3
= 31
b,
(12x+84+55):5=35
12x+84+55=35.5
12x+84+55=175
12x=175-55-84
12x=36
x=36:12
x=3
a)123 -5(x+4)=38
b)(3x-24).73=2.73
a)123 -5(x+4)=38
5(x+4)=123-38
5(x+4)=85
x+4=17
x=17-4
x=13
Vậy x=13
b)(3x-24).73=2.73
(3x-24)=2.73:73
(3x-24)=2
3x=2+24
3x=18
x=6
Vậy x=6
tim so tu nhien x biet
a.123-5.(x+4)=38
b.(3.x-24).73=2.74
a.
123-5.(x+4)=38
=>5.(x+4)=123-68
=>5.(x+4)=85
=>x+4=85:5
=>x+4=17
=>x=17-4
=>x=13
b. (3.x-24).73=2.74
=>3.x-16=2.74:73
=>3.x-16=14
=>3.x=14+16
=>3.x=30
=>x=30:3
=>x=10
Tìm số tự nhiên x
123 - 5 . ( x + 4 ) = 38
(3x - 24 ) .73 = 2.74
123 - 5(x + 4) = 38
=> 5(x + 4) = 85
=> x + 4 = 17
=> x = 13
vậy_
(3x - 24).73 = 2.74
=> 3x - 16 = 2.74 : 73
=> 3x - 16 = 2.7
=> 3x - 16 = 14
=> 3x = 30
=> x = 10
vậy_
a)123 - 5 . ( x + 4 ) = 38
5 . ( x + 4 ) = 123 - 38
5 . ( x + 4 ) = 85
x + 4 = 85 : 5
x + 4 =17
x = 13
b) ( 3x - 2^4 ) . 7^3 = 2 . 7^4
( 3x - 2^4 ) = 2 . 7^4 : 7^3
( 3x - 2^4 ) = 2 . 7
3x - 2^4 = 14
3x - 16 = 14
3x = 30
x = 30 : 3
x = 10
123 - 5.(x+4) = 38
5.(x+4) = 85
x + 4 = 17
x= 13
(3x - 24).73 = 2.74
3x - 24 = 14
3x = 30
x = 10
Tìm số tự nhiên \(x\) , biết :
a) \(123-5\left(x+4\right)=38\)
b) \(\left(3.x-2^4\right).7^3=2.7^4\)
a) \(123-5\left(x+4\right)=38\)
\(5\left(x+4\right)=123-38\)
\(5\left(x+4\right)=85\)
\(x+4=85:5\)
\(x+4=17\)
\(x=17-4\)
\(x=13\)
Vậy \(x=13\).
b) \(\left(3x-2^4\right)\cdot7^3=2\cdot7^4\)
\(3x-16=2\cdot7^4:7^3\)
\(3x-16=2\cdot7\)
\(3x-16=14\)
\(3x=14+16\)
\(3x=30\)
\(x=30:3\)
\(x=10\)
Vậy \(x=10\).
Tìm x , biết :
a) 5 . ( x + 4 ) = 123 - 38
b) \(3.x-16=2.7^4:7^3\)
k mik mik ki lại nha hi hi
a) Ta có: 5 .(x+4) = 123 - 38
5 .(x+4) = 85
x+4 = 85 : 5
x+4 = 17
x = 17 - 4
x = 13
Câu b: Tương tự
a) 5 . ( x + 4 ) = 123 - 38
5 . ( x + 4 ) = 85
x + 4 = 85 : 5
x + 4 = 17
x = 17 - 4
x = 13
b ) \(3.x-16=2.7^4:7^3\)
3 . x - 16 = 2 . 7
3 . x - 16 = 14
3 . x =14 + 16
3 . x = 30
x = 30 : 3
x = 10
k mik nhé các bn I LVE YOU VERY MUCH
1. Tìm x, biết 1+2+3+...+x=2021055
2. Tìm x, biết
a) 123-5.(x+4)=38
b) (3x-24).73=2.73
3.Tìm số dư của phép chia sau đây 123456789987654321:2015
1. tìm x
kết quả x là : 2010
2. tìm x
a) x = 13
b) x = 6
đúng ko
câu 3 số lớn quá
1.
1(1+2+3+4+....+x)=2021055
1+2+3+4+....+x=2021055:1=2021055
x+(x+1)/1=2021055
=>x(x+1)=1*2021055=2021055=2011*2010 =>x=2010
3.Tìm số dư123456789987654321 : 2015
123456789:2015=61268,R= 1769
176998765:2015=87840,R= 1165
11654321:2015=5783,R= 1576
Vậy số dư của phép chia 123456789987654321:2015 là 1576
1. Tìm số tự nhiên X biết
A )123 -5 ( x -4 ) = 38
B ) ( 3x - 24 ) 73 = 2.74
C ) ( 2600 + 6400 ) - 3x = 1200
D ) [( 6x - 72 ) : 2 - 84 ] 28 = 5628
A )123 -5 ( x -4 ) = 38
=> x-4 = (123-38) :(-5)
=> x-4=-17
=> x= -17+4=-13
B ) ( 3x - 24 ) 73 = 2.74
=> 3x-16= 2.74 :73=14
=> 3x=14+16=30
=> x=30:3=10
C ) ( 2600 + 6400 ) - 3x = 1200
=> 9000-3x=1200
=> 3x=9000-1200=7800
=> x=7800:3=2600
D ) [( 6x - 72 ) : 2 - 84 ] 28 = 5628
=> (6x-72) :2-84= 5628:28=201
=> 6x-72 = (201+84) .2=570
=> 6x=570 +72=642
=> x= 642:6=107
( L-IKE )
A) 123 - 5(x-4) = 38
5(x-4) = 123 - 38
x-4 = 85 : 5
x = 17 + 4
x= 21
B) (3x - 24)73 = 2.74
(3x - 24) = 2.74:73
3x = 14 + 24
x = 30 : 3 = 10
C) (2600 + 6400) - 3x = 1200
9000 - 3x = 1200
3x = 9000 - 1200
x = 7800 : 3 = 2600
D) [(6x - 72) : 2 - 84].28 = 5628
(6x - 72) : 2 - 84 = 5628 : 28 = 201
(6x - 72) : 2 = 201 + 84 = 285
6x - 72 = 285 . 2 = 570
6x = 570 + 72 = 642
x = 642 : 6 = 107
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