Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\frac{8}{12}\cdot x\cdot4-\frac{18}{12}\cdot x\cdot6=\frac{5}{12}\)
\(x\left(\frac{8}{12}\cdot4-\frac{18}{12}\cdot6\right)=\frac{5}{12}\)
\(x\left(\frac{32}{12}-\frac{108}{12}\right)=\frac{5}{12}\)
\(x\left(-\frac{19}{3}\right)=\frac{5}{12}\)
\(x=\frac{5}{12}\div\left(-\frac{19}{3}\right)=-\frac{5}{76}\)
Vậy \(x=-\frac{5}{76}\)
Chúc bạn học tốt ^^!!!
\(\frac{3}{3.6.9}+\frac{3}{6.9.12}+\frac{3}{9.12.15}+\frac{3}{12.15.18}=\frac{3}{6}\left(\frac{6}{3.6.9}+\frac{6}{6.9.12}+\frac{6}{9.12.15}+\frac{6}{12.15.18}\right)\)
= \(\frac{1}{2}\left(\frac{1}{3.6}-\frac{1}{6.9}+\frac{1}{6.9}-\frac{1}{9.12}+\frac{1}{9.12}-\frac{1}{12.15}+\frac{1}{12.15}-\frac{1}{15.18}\right)\)
\(=\frac{1}{2}\left(\frac{1}{3.6}-\frac{1}{15.18}\right)=\frac{1}{2}.\frac{14}{270}=\frac{7}{270}\)
1) 3(x - 4) - (8 - x) = 12
3x - 12 - 8 + x = 12
4x - 20 = 12
4x = 12 + 20
4x = 32
x = 8
2) 5(x - 6) - 2(x + 3) = 12
5x - 30 - 2x - 6 = 12
3x - 36 = 12
3x = 12 + 36
3x = 48
x = 16
3) 5 - | x + 7| = 4
|x + 7| = 4 - 5
|x + 7| = -1 x + 7 = 1; -1 x + 7 = 1 hoặc x + 7 = -1 x = 1 - 7 x = -1 - 7 x = -6 x = -8 => x = -6 hoặc x = -8 4) 6|x - 7| = 18 : (-3) 6|x - 7| = -6 6|x - 7| = -6 : 6 |x - 7| = -1 x - 7 = 1; -1 x - 7 = 1 hoặc x - 7 = -1 x = 1 + 7 x = -1 + 7 x = 8 x = 6 => x = 8 hoặc x = 6Trả lời
A.12:(x+4).3=6
12:(x+4) =6:3
12:(x+4) =2
x+4 =12:2
x+4 =6
x =6-4
x =2
a) 12 : (x + 4).3 = 6
\(\frac{12}{\left(x+4\right)}.3=6\)
\(\frac{36}{\left(x+4\right)}=6\)
x + 4 = 36 : 6
x + 4 = 6
x = 6 - 4
x = 2
b) 12 : (x + 4).3 = 5
\(\frac{12}{\left(x+4\right)}.3=5\)
\(\frac{36}{\left(x+4\right)}=5\)
x + 4 = 36 : 5
x + 4 = \(\frac{36}{5}\)
x = \(\frac{36}{5}\) - 4
x = \(\frac{16}{5}\)
c) 12 : (x + 4).3 + 18 = 24
\(\frac{12}{\left(x+4\right)}.3+18=24\)
\(\frac{18x+108}{x+4}=24\)
18x + 108 = 24x + 96
18x + 108 - 24x = 96
-6x + 108 = 96
-6x = 96 - 108
-6x = -12
x = -12 : -6
x = 2
1) 9 . (x + 7) - 12 = 24
9 . (x + 7) = 24 + 12
9 . (x + 7) = 36
x + 7 = 36 : 9
x + 7 = 4
x = 4 - 7
x = -3
2) 12 - 3x = -30
3x = 12 - (-30)
3x = 12 + 30
3x = 42
x = 42 : 3
x = 14
3) 95 - 105 : x = 60
105 : x = 95 - 60
105 : x = 35
x = 105 : 35
x = 3
4) x + 35 = 12
x = 12 - 35
x = -23
5) (-24) - (10 - x) = 43
-24 - 10 + x = 43
-34 + x = 43
x = 43 - (-34)
x = 43 + 34
x = 77
6) 6 - (17 + x) = -16
6 - 17 - x = -16
-11 - x = -16
x = -11 - (-16)
x = -11 + 16
x = 5
7) (x - 18) - (-3) = 0
x - 18 + 3 = 0
x - 18 = 0 - 3
x - 18 = -3
x = -3 + 18
x = 15
8) 25 - (x - 6) = -1
25 - x + 6 = -1
25 - x = -1 - 6
25 - x = -7
x = 25 - (-7)
x = 25 + 7
x = 32
1)9.(x+7)-12=24
9.(x+7)=24+12
9.(x+7)=36
x+7=36:9
x+7=4
x=4-7
x=-3
1) = 35 . 18 - 35 . 18 = 0
2) = 45 - 5 . 12 + 5 . 9 = 45 - 60 + 45 = 30
3) = 24 . 16 - 24 . 5 - 16 . 24 - 16 . 5
= (24 . 16 - 16 . 24) - 5 (24 - 16)
= 0 - 5 . 8 = 0 - 40 = -40
4) = 29 . 19 - 29 . 13 - 19 . 29 - 19 . 13
= (29 . 19 - 29 . 19) - 13 (29 - 19)
= 0 - 13 . 10 = 0 - 130 = -130
5) = 31 . (-18) + 31 . (-81) - 31 . 1
= 31 [(-18) + (-81) - 1]
= 31 . (-100) = -3100
6) = (-12) . 47 + (-12) . 52 + (-12). 1
= (-12) . (47 + 52 + 1)
= (-12) . 100 = -1200
7) = 13 . 45 - 3 . 45
= 45 (13 - 3)
= 45 . 10 = 450
8) = (-48) + 48 . (-78) + 48 . (-21)
= (-48) . 1 + 48 . (-78) + 48 . (-21)
= 48 . (-1) + 48 . (-78) + 48 . (-21)
= 48 . [(-1) + (-78) + (-21)]
= 48 . (-100) = -4800
1) 35x18-5x7x18
= 35x18-35x18
= 35x(18-18)
= 35x0=0
3) 24.(16-5)-16.(24-5)
= 24.16-24.5-16.24-16.5
=[24.16-16.24]-[24.5-16.5]
= [ 24. (16-16)]- [(24-16).5]
= [24.0]-[8.5]
= 0-40=-40
4) 29.(19-13)-19.(29-13)
=29.19-29.13-19.29-19.13
=[ 29.19-19.29]-[ 29.13-19.13]
= [ 29.(19-19)]-[(29-19).13]
=[29.0]-[10.13]
= 0-130= -130
5) 31.(-18)+31.(-81)-31
= 31.(-18)+31.(-81)-31.1
= 31.[(-18)+(-81)-1]
=31.(-100)
= -3100
6);7);8 tương tự 4);5);6)
Tìm số nguyên x, biết:
1) -16 + 23 + x = - 16
7+x=-16
x=-16-7
x=-23
2) 2x – 35 = 15
2x=15+35
2x=50
x=50:2
x=25
3) 3x + 17 = 12
3x=12-17
3x=-5
x=-5/3
4) (2x – 5) + 17 = 6
2x-5=6-17
2x-5=-11
2x=-11+5
2x=-6
x=-6:2
x=-3
5) 10 – 2(4 – 3x) = -4
2(4-3x)=10-(-4)
2(4-3x)=14
4-3x=14:2
4-3x=7
3x=4-7
3x=-3
x=-3:3
x=-1
6) - 12 + 3(-x + 7) = -18
3(-x+7)=-18-(-12)
3(x+7)=-6
x+7=-6:3
x+7=-2
x=-2-7
x=-9