Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
B2:tìm x biết
1)x+18=6-2x
<=> 3x=-12
<=> x= -4
2)17-x=7-6x
<=>5x=-10
<=>x=-2
3)x+15=20-4x
<=>5x=5
<=>x=1
4)7x-4=20+3x
<=> 4x=24
<=>x=6
5)-12+x=5x-20
<=>4x=8
<=>x=2
6)4x-18=x+27
<=>3x=45
<=>x=9
7) 2.(x-5)-3.(x+7)=14
<=>2x-10-3x-21=14
<=>-x=14+10+21=45
<=>x=-45
8)5.(x-6)-2.(x+3)=12
<=>5x-30-2x-6=12
<=>3x=48
<=>x=12
9)-7.(5-x)-2.(x-10)=15
<=>-35+7x-2x+20=15
<=>5x=30
<=>x=6
10)3. ( x - 4 ) - ( 8 - x )=12
<=>3x-12-8+x=12
<=>4x=32
<=>x=8
11)4.(x-5)-(x+7)=-19
<=>4x-20-x-7=-19
<=>3x=8
<=>x=8/3
12)7.(x-3)-5.(3-x)=11x-5
<=>7x-21-15+5x=11x-5
<=>x=31
b1:bỏ ngoặc rồi tinh hợp lí
1) -( -66)+34+(-73)-27+99=66+34-73-27+99 =100-100+99=99
2)54-(45-30+54)-30+5=54-45+30-54-30+5=-45+5=-40
3)42-56+33-(33-56+42)=42-56+33-33+56-42=0
4)50-(47+50-18)+(47-18)=50-47-50+18+47-18=0
5) |25-24-10|-(28-30+4)=9-28+30-4=39-32=7
6)-(-73)+(44-94+27)+94=73+44-94+27+94=100+44=144
7) (-33+180-75)-(180+25)=-33+180-75-180-25=-100-33=-133
8)120-(-92+120-18)-92=120+92-120+18=108
47. (23 + 50)- 23. ( 47+50 )
= 47. 23+ 47. 50- 23. 47 - 23. 50
=47. 50 - 23. 50
= 50 .( 47 -23)
=50. 24 = 1200
Bài 1 :
a, 25 + (-42) = - ( 42 - 25 ) = - 17
b, (-17) + 5 + 8 + 17 + (-3 )
= [ (-17) + 17 ] + [ ( 5 + 8 ) + (-3) ]
= 0 + 10
= 10
c, 25. 22 - ( 15-18 ) + ( 12 - 19 + 10 )
= 25 . 4 - (-3) + 3
= 100 - [ (-3) + 3 ]
= 100 - 0
= 100
d, 120 - 35 + 29 - 242
= 85 + 29 - 242
= 114 - 242
= -128
a) 54 + ( 218 - x ) = 735
218 - x = 735 - 34
218 - x = 701
x = 218 - 701
x = -483
b) 96 - 3 ( x + 1 ) = 42
3 ( x + 1 ) = 96 - 42
3 ( x + 1 ) = 54
x + 1 = 54 : 3
x + 1 = 18
x = 18 - 1
x = 17
c) 5 ( x + 35 ) 515
x + 35 = 515 : 5
x + 35 = 103
x = 103 - 35
x = 68
d) 12x - 33 = 32 . 32
12x - 33 = 9.9
12x - 33 = 81
12x = 81 + 33
12x = 114
x = 114 : 12
x = 9,5
a) 54+(218-x)=735
218-x=681
x=-463
b) 96-3(x+1)=42
3(x+1)=54
x+1=18
x=17
c) 5(x+35)=515
x+35=103
x=68
d) 12x-33=3^2.2^2
12x-33=81
12x = 114
x=9,5
Nhấn đúng cho mk nha!!!!!!!!
a, \(x\) + 99: 3 = 55
\(x\) + 33 = 55
\(x\) = 55 - 33
\(x\) = 22
b, (\(x\) - 25):15 = 20
\(x\) - 25 = 20 x 15
\(x\) - 25 = 300
\(x\) = 300 + 25
\(x\) = 325
c, (3\(x\) - 15).7 = 42
3\(x\) - 15 = 42:7
3\(x\) - 15 = 6
3\(x\) = 6 + 15
3\(x\) = 21
\(x\) = 21: 3
\(x\) = 7
1. 11(x-9)=77
x-9=7
x=16
2. 4(x-3)=48
x-3=12
x=15
3.3(x-8)=81
(x-8)=27
x=35
99 - 3(x + 17) = 45
=> 3(x + 17) = 99 - 45
=> 3x + 51 = 54
=> 3x = 54 - 53
=> 3x = 3
=> x = 3 : 3
=> x = 1
vậy_
a,99-3x-51=45
3x=45+51-99
3x=-3
x=-1
b,x5:8=4
x5=32
x=2
c,3.x3=375
x3=125
x=5
d,12.x-33=35
12x=276
x=23
e,4x5=128
x5=32
x=2
g,2x:4=16
2x=64
x=6