Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
`@` `\text {Ans}`
`\downarrow`
`a)`
`x + 10 = 20`
`=> x = 20 -10`
`=> x = 10`
Vậy, `x = 10`
`b)`
`2 * x + 15 = 35`
`=> 2x = 35 - 15`
`=> 2x = 20`
`=> x = 20 \div 2`
`=> x = 10`
Vậy, `x = 10`
`c)`
`3 * ( x + 2 ) = 15`
`=> x + 2 = 15 \div 3`
`=> x + 2 = 5`
`=> x = 5 - 2`
`=> x = 3`
Vậy, `x = 3`
`d)`
`10 * x + 15 * 11 = 20 * 10`
`=> 10x + 165 = 200`
`=> 10x = 200 - 165`
`=> 10x = 35`
`=> x = 35 \div 10`
`=> x = 3,5`
Vậy,` x = 3,5`
`e)`
`4 * ( x + 2 ) = 3 * 4`
`=> x + 2 = 12 \div 4`
`=> x + 2 = 3`
`=> x = 3 - 2`
`=> x = 1`
Vậy,` x = 1`
`f)`
`33 x + 135 = 26 * 9`
`=> 33x + 135 = 234`
`=> 33x = 234 - 135`
`=> 33x = 99`
`=> x = 99 \div 33`
`=> x = 3`
Vậy, `x = 3`
`g)`
`2 * x + 15 + 16 + 17 = 100`
`=> 2x + 48 = 100`
`=> 2x = 100 - 48`
`=> 2x = 52`
`=> x = 52 \div 2`
`=> x =26`
`h)`
`2 * (x + 9 + 10 + 11) = 4 . 12 . 25`
`=> 2 * (x + 9 + 10 + 11) = 4*25*12`
`=> 2 * (x + 9 + 10 + 11) = 100*12`
`=> x + 9 + 10 + 11 = 100*12 \div 2`
`=> x + 30 = 600`
`=> x = 600 - 30`
`=> x = 570`
Vậy, `x = 570.`
a) \(x+10=20\Leftrightarrow x=10\)
b) \(2x+15=35\Leftrightarrow2x=20\Leftrightarrow x=10\)
c) \(3.\left(x+2\right)=15\Leftrightarrow x+2=5\Leftrightarrow x=3\)
d) \(10x+15.11=20.10\Leftrightarrow10x+165=200\Leftrightarrow10x=35\Leftrightarrow x=\dfrac{35}{10}=\dfrac{7}{2}\)
e) \(4.\left(x+2\right)=3.4\Leftrightarrow x+2=3\Leftrightarrow x=1\)
f) \(35x+135=26.9\Leftrightarrow35x=234-135\Leftrightarrow35x=99\Leftrightarrow x=\dfrac{99}{35}\)
g) \(2x+15+16+17=100\Leftrightarrow2x+48=100\Leftrightarrow2x=52\Leftrightarrow x=26\)
h) \(2.\left(x+9+10+11\right)=4.12.25\)
\(\Leftrightarrow x+30=2.12.25\)
\(\Leftrightarrow x=600-30\)
\(\Leftrightarrow x=570\)
a) x + 10 = 20
<=> x = 20 - 10 = 10
Vậy x = 10
b) 2x + 15 = 35
<=> 2x = 35 - 15 = 20
<=> x = 10
Vậy x = 10
c) 3(x + 2) = 15
<=> x + 2 = 15 : 3 = 5
<=> x = 5 - 2 = 3
Vậy x = 3
d) 10x + 15.11 = 20.10
<=> 10x + 165 = 200
<=> 10x = 200 - 165 = 35
<=> x = 35 : 10 = 3,5
Vậy x = 3,5
e) 4(x + 2) = 3.4
<=> x + 2 = 3
<=> x = 3 - 2 = 1
Vậy x = 1
f) 33x + 135 = 26.9
<=> 33x + 135 = 234
<=> 33x = 234 - 135 = 99
<=> x = 99 : 33 = 3
Vậy x = 3
g) 2x + 15 + 16 + 17 = 100
<=> 2x + 48 = 100
<=> 2x = 100 - 48 = 52
<=> x = 52 : 2 = 26
Vậy x = 26
h) 2(x + 9 + 10 + 11) = 4.12.5
<=> x + 30 = 120
<=> x = 120 - 30 = 90
Vậy x = 90
(-15)\(x\) = - 45
\(x\) = - 45 : (-15)
\(x\) = 3
Vậy \(x=3\)
(-15)\(x\) = 10.(-40).(-5)
-15\(x\) = -400.(-5)
-15\(x\) = 2000
\(x\) = 2000 : (-15)
\(x\) = - \(\dfrac{400}{3}\)
Vậy \(x=-\dfrac{400}{3}\)
a, 48.84
= (22)8.(23)4
= 216.212
= 228
b, 415.515
= (4.5)15
= 2015
c, 210.15 + 210.85
= 210.(15 + 85)
= 210.100
=210.(2.5)2
= 212.52
d, 33.92
= 33 . (32)2
= 33.34
= 37
e, 512.7 - 511.10
= 511.(5.7 - 10)
= 511.25
=511.52
=513
f, \(x^1\).\(x^2\).\(x^3\)....\(x^{100}\)
= \(x^{1+2+3+...+100}\)
= \(x^{\left(1+100\right).100:2}\)
= \(x^{5050}\)
Bài 1:
a: BCNN(10;12)=60
b: BCNN(24;10)=120
c: BCNN(4;14;26)=364
d: BCNN(6;8;10)=120
=>(x-3)+(x-2)+(x-1)+...+10=15-15=0
={[10+(x-3)]x số số hạng} :2
vì số số hạng khác 0=>10+(x+3)=0=>x-3=0-10=-10=>x=-10+3=-7
vậy x=-7
a, x+15=20-4x
=> x + 4x = 20 - 15
=> 5x = 5
=> x = 5 : 5
=> x = 1
b, 17-x=7-6x
=> -x + 6x = 7 - 17
=> 5x = - 10
=> x = -10 : 5
=> x = -2
c, 4.(x-5)-3.(x+7)= -19
=> 4x - 4.5 - 3.x + 3.7 = -19
=> 4x - 20 - 3x + 21 = -19
=> (4x-3x) + (21-20) = -19
=> 1x + 1 = -19
=> x = -19 - 1
=> x = -18
d, -7.(5-x)-2.(x-10)=15
=> -7x - (-7).5 - 2x - 2.10 = 15
=> -7x - (-35) - 2x - 20 = 15
=> -7x + 35 - 2x - 20 = 15
=> -7x+2x + (35-20) = 15
=> -5x + 15 = 15
=> -5x = 15 - 15
=> -5x = 0
=> x = 0 : (-5)
=> x = 0
e, -5.(2-x)+4.(x-3) = 10.x-15
=> -5x - (-5).2 + 4x - 4.3 = 10x - 15
=> -5x - (-10) + 4x - 12 = 10x - 15
=> -5x + 10 + 4x - 12 = 10x - 15
=> (-5x+4x) - (12-10) = 10x - 15
=> -1x - 2 = 10x - 15
=> -1x - 10x = -15 + 2
=> -11x = -13
=> x = \(\frac{-13}{-11}\)
x + 10 = 15 x 2
x + 10 = 30
x = 30 - 10
x = 20
x +10 = 30
=> x = 30 - 10
=> x = 20