Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a, |3x - 6| + 4x + 3 = 12
|3x - 6| = 12 - 3 - 4x
|3x - 6| = 9 - 4x
TH1: 3x - 6 = 9 - 4x ⇔ 3x + 4x = 9 + 6 ⇔ 7x = 15 ⇔ x = 15/7
TH2: 3x - 6 = 4x - 9 ⇔ 3x - 4x = -9 + 6 ⇔ -x = -3 ⇔ x = 3.
b, |6x - 12| + 3x - 1 = 43
|6x - 12| = 43 + 1 - 3x
|6x - 12| = 44 - 3x
TH1: 6x - 12 = 44 - 3x ⇔ 6x + 3x = 44 + 12 ⇔ 9x = 56 ⇔ x = 6.
TH2: 6x - 12 = 3x - 44 ⇔ 6x - 3x = -44 + 12 ⇔ 3x = -32 ⇔ x = -32/3.
c, |8 - 4x| + 7x - 5 = 16 - 2x
|8 - 4x| = (16 + 5) + (-2x - 7x)
|8 - 4x| = 21 - 9x
TH1: 8 - 4x = 21 - 9x ⇔ -4x + 9x = 21 - 8 ⇔ 5x = 13 ⇔ x = 13/5
TH2: 8 - 4x = 9x - 21 ⇔ -4x - 9x = -21 - 8 ⇔ -15x = -29 ⇔ x = 29/15
a) \(6x-36=5^{12}:5^{10}-2012^0\)
\(6x-36=5^2-2012^0\)
\(6x-36=25-1\)
\(6x-36=24\)
\(6x\) \(=24+36\)
\(6x\) \(=60\)
\(x=60:6\)
\(x=10\)
Vậy \(x=10\)
b) \(2x-125=-65\)
\(2x\) \(=\left(-65\right)+125\)
\(2x\) \(=60\)
\(x=60:2\)
\(x=30\)
Vậy \(x=30\)
c) \(2012-120\left(4x+1\right)=932\)
\(120\left(4x+1\right)=2012-932\)
\(120\left(4x+1\right)=1080\)
\(4x+1=1080:120\)
\(4x+1=9\)
\(4x\) \(=9-1\)
\(4x\) \(=8\)
\(x=8:4\)
\(x=2\)
Vậy \(x=2\)
a) 6x - 36 = 512 : 510 - 20120
6x - 36 = 52 - 20120
6x - 36 = 25 - 1
6x - 36 = 24
6x = 24 + 36
6x = 60
x = 60 : 6
x = 10
Vậy x = 10
b) 2x - 125 = -65
2x = (-65) + 125
2x = 60
x = 60 : 2
x = 30
Vậy x = 30
c) 2012 - 120(4x + 1) = 932
120(4x + 1) = 2012 - 932
120(4x + 1) = 1080
4x + 1 = 1080 : 120
4x + 1 = 9
4x = 9 - 1
4x = 8
x = 8 : 4
x = 2
Vậy x = 2.
Chúc bạn học tốt!
2 . 53 . 27 + 6 . 9 . 87 - 3 . 18 . 40
= 2. 53 . 9 . 3 + 2. 3 .9 .87 - 3 .2 .9 .40
= 54.53+54.87-54.40
=54(53+87-40)
=54. 100=5400
12 . 25 + 29 . 25 + 59 . 25
= 25 . ( 12+29+59)
=25 . 90
=2250
43 . 37 + 93 . 43 + 57 . 61 + 69 . 57
= 43.(37+93)+57(61+69)
=43.130+57.130
=130.(43+57)
=130.100
=13 000
12 . 53 + 53 . 172 - 53
=53(12+172-1)
=53.184
=9752
35 . 54 + 35 . 58 + 65 . 75 + 65 . 45
=35(54+58)+65(75+45)
=35.112+65.120
=3920+7800
=11720
39 . 8 + 70 . 3 + 31 . 8
=8(39+31)+70.3
=8.70+70.3
=70.(8+3)
=70.11
=770
=77(5x7+65)-21x57-21x43
=77x100-(21x57+21x43)
=7700-21(57+43)
=7700-21.100
=7700-2100
=5600
6.4\(x\).41 + 4\(^x\).4\(^3\) = 28.(7 + 15)
4\(^x\).(6.4 + 43) = 28.22
4\(^x\).(24 + 64) = 256.22
4\(^x\). 88 = 5632
4\(^x\) = 532 : 88
4\(^x\) = 64
4\(^x\) = 43
\(x\) = 3
a: 3x=81
nên x=27
b: \(5\cdot4^x=80\)
\(\Leftrightarrow4^x=16\)
hay x=2
c: \(2^x=4^5:4^3\)
\(\Leftrightarrow2^x=2^4\)
hay x=4
a) \(19.43+\left(-20\right).43-\left(-40\right)\)
\(=43.\left(19-20\right)+40\)
\(=-43+40\)
\(=-3\)
b) \(6^7:6^5+3.3^2-2021^0\)
\(=6^2+3^3-1\)
\(=36+27-1\)
\(=62\)
c) \(465+\left[\left(-38\right)+\left(-465\right)\right]-\left[12-\left(-42\right)\right]\)
\(=465-38+\left(-465\right)-12-42\)
\(=-92\)
1. Thực hiện phép tính bằng cách hợp lí :
a) (-46) + (-125) + 46 + 25 = [(-46)+46] + [(-125)+25]
= 0+(-100) = -100
b) 25.(-15) + 25.(-5) + (-20).75 = 25.[(-15)+(-5)] + (-20).75
= 25.(-20) + (-20).75 = (-20).(25+75) = (-20).100 = -2000
c) (-151)+(-37)+(-42)+(-63)+142 =(-151)+[(-37)+(-63)]+[(-42)+142]
= (-151) + [(-100) + 100] = -151
d)32+(-149)+(-311)+(-89)+(-51) = 32+[(-149)+(-51)] + [(-311)+(-89)]
= 32+[(-200)+(-400)] = 32+(-600) = -568
e)-65.(87-17)-87.(17-65) = (-65).87 - (-65).17 - 87.17 + 87.65
= (-65).87 + 65.17 - 87.17 + 87.65 = [(-65).87+87.65] + 65.(17-87)
= 65.(-70) = -4550
g) -43.(53-16) - 53.(16-43) = (-43).53 - (-43).16 - 53.16 + 53.43
= (-43).53 + 43.16 - 53.16 + 53.43 = [(-43).53+53.43] + 16.(43-53)
= 16.(-10) = -160