Tìm x
1+40÷x=21
2×x-138=2^3×3^2
10+2×x=4^5÷4^3
10×x-20=10^2
42=39×42-37×42
(X-5)-100=0
231-(x-6)=1339÷13
8 (x-3)=0
123-5.(x+4)=38
10+2x=2.(32-1)
2.x-138=23.32
[102+(28-2x)]:20-5=1
231-(x-6)=1339:13
123-5.(x+4)=38
5(x+4)=123-38
5(x+4)=85
x+4=85:5
x+4=17
x=17-4
x=13
10+2x=2.(32-1)
10+2x=2.(9-1)
10+2x=2.8
2x=16-10
2x=6
x=6:2
x=3
2.x-138=23.32
2.x-138=72
2.x=72+138
2.x=210
x=210:2
x=105
[102+(28-2x)]:20-5=1
(102+28-2x):20=6
130-2x=120
2x=130-120
2x=10
x=10:2
x=5
231-(x-6)=1339:13
231-(x-6)=103
x-6=231-103
x-6=128
x=128+6
x=134
123-5.(x+4)=38
5.(x+4)=123-38
5.(x+4)=85
(x+4)=85/5
x+4=17
x=17-4
x=13
10 + 2x = 2(32 - 1)
=> 10 + 2x = 2(9 - 1)
=> 10 + 2x = 2.8
=> 10 + 2x = 16
=> 2x = 16 - 10
=> 2x = 6
=> x = 6/2
=> x = 3
1.Tìm x
a) 310-(118-x)=217
b) 814-(x-305)=712
c)5(x+35)=515
d)(6.x-39):3].28=5628
e)2.x-138=23.22
g)20-[7.(x-3)+4]=2
a) 310-(118-x)=217
118-x=310-217
118-x=93
x=118-93
x=25
b) 814-(x-305)=712
x-305=814-712
x-305=102
x =102+305
x = 407
c)5(x+35)=515
x+35 =515:5
x+35 =103
x =103-35
x =68
\(a,310-\left(118-x\right)=217\) \(c,5\left(x+35\right)=515\)
\(118-x=310-217\) \(x+35=515:5\)
\(118-x=93\) \(x+35=103\)
\(x=118-93\) \(x=103-35\)
\(x=25\) \(x=68\)
\(b,814-\left(x-305\right)=712\) \(\left[\left(6.x-39\right):3\right].28=5628\)
\(x-305=814-712\) \(\left(6.x-39\right):3=5628:28\)
\(x-305=102\) \(\left(6.x-39\right):3=201\)
\(x=102+305\) \(6.x-39=201x3\)
\(x=407\) \(6.x-39=603\)
\(6x=603+39\)
\(6x=642\)
\(x=107\)
\(e,2.x-138=2^3.2^2\)
\(2.x-138=32\)
\(2.x=32+138\)
\(2.x=170\)
\(x=170:2\)
\(x=85\)
310 - ( 118-x) = 217
118 - x = 310 - 217
118 -x = 93
x = 118 - 93
x = 25
Bài 10: Tìm số tự nhiên x, biết:
a) 70 – 5 . (x – 3) = 45 b) 2 . x – 138 = 2 ^3 . 3^ 2 c) 10 + 2 . x = 4 ^5 : 4 ^3d) 231-( x-6) = 1339: 13a,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
Vậy x = 8
b,\(2x-138=8x9=72\)
\(2x=138+72=210\)
\(x=210:2=105\)
c,\(10+2x=4^2\)\(=16\)
\(2x=16-10=6\)
\(x=6:2=3\)
d, 231 – (x- 6) = 1339 : 13
231 – (x – 6) = 103
x – 6 = 231 – 103
x – 6 = 128
x = 128 + 6
x = 134
Vậy x = 134
a) 10+2.x=4 mũ 5 4 mũ 3
b)2.x-138= 2 mũ 3. 3 mũ 2
c)231-(x-6)=1339:13
Bài 3. Tìm x biết:
1) |x| = 10 2) |x - 8| = 0 3) 7 + |x| = 12
4) |x + 1| = 3 5) 15 - x = 16 - (14 - 42) 6) 210 - (x - 12) = 168
1/ `|x|=10<=> x=\pm 10`
2/ `|x-8|=0<=>x-8=0<=>x=8`
3/ `7+|x|=12<=>|x|=5<=>x=\pm 5`
4/ `|x+1|=3`
$\Leftrightarrow\left[\begin{array}{1}x+1=3\\x+1=-3\end{array}\right.\\\Leftrightarrow\left[\begin{array}{1}x=3\\x=-4\end{array}\right.$
5/ `15-x=16-(14-42)`
`<=>15-x=16+28`
`<=>15-x=44`
`<=>x=-29`
6/ `210-(x-12)=168`
`<=>210-x+12=168`
`<=>222-x=168`
`<=>x=54`
1.
\(\left|x\right|=10\Leftrightarrow x=\pm10\)
2.
\(\left|x-8\right|=0\Leftrightarrow x-8=0\Leftrightarrow x=8\)
3.
\(7+\left|x\right|=12\Leftrightarrow\left|x\right|=5\Leftrightarrow x=\pm5\)
Có ai giúp mình k ạ:
Bài 1: Tìm x
A,2.x-138=2 mũ3 . 3 mũ 2
B,10+2.x= 4mũ 5 ÷4 mũ 3
C, 70-5.(x-3) = 45
D, 21-(x-6)=1339÷13
2x - 138 = 23 . 32
2x - 138 = 72
2x = 72 + 138
2x = 210
x = 105
10 + 2x = 45 : 43
10 + 2x = 16
2x = 16 - 10
2x = 6
x= 3
tim x
2.x-138=23.32
231-(x-6)=1339:13
50(x-3)+40=160
(32:3):(x-35.)+20=21
áp dụng tính chất chia hết xem xét mỗi tổng sau có chia hết cho 7 không
35+49+210
42+50+140
cho tong A=12+14+16+x voi x \(\in\)N
A chia hết cho 2
A không chia hết cho 2
2x - 138 = 23 . 32
\(\Rightarrow\) x - 69 = 22 . 9 = 4 . 9
\(\Rightarrow\) x - 69 = 36
\(\Rightarrow\) x = 105
231 - (x - 6) = 1339 : 13
\(\Rightarrow\) 231 - (x - 6) = 103
\(\Rightarrow\) x - 6 = 128
\(\Rightarrow\) x = 134
50(x - 3) + 40 = 160
\(\Rightarrow\) 50(x - 3) = 120
\(\Rightarrow\) x - 3 = 2,4
\(\Rightarrow\) x = 5,4
Tìm số tự nhiên x, biết:
a) (2600 + 6400) - 3 . x = 1200
b) [(6 . x - 72) : 2 -84] . 28 = 5628
c) 2x - 138 = 23 . 32
d) 42x = 39 . 42 - 37 . 42
ai cho 2 cái để được hai điểm hỏi đáp
1, (2+4+6+...+100)
2, 10-(3-x)=-10+17
3, 17-(3+x)=2-(7-8)
4, (5+x)-(15-31)=-20
5, 17-(3+x)+15-3=2
6, (41-x)-(13-17)=40-50
7, -(52-x)+(40-42)=-57+13