9 . 520 . 279 - 3 . 915 . 259
7 . 329 . 1256 - 3 . 39 .1519
Tìm x
24.X - 32. X = 145-255:51
580:(X-24)=329-150:2
7.(X-4)+35=25+279:9
24.x-32.x=145-255:51
16.x-9.x=145-5
16.x-9.x=140
x.(16-9)=140
x.7=140
x=140:7
x=20
580:(x-24)=329-150:2=ko bít
7.(x-4)+35=25+279:9
7.(x-4)+35=25+31
7.(x-4)+35=56
7.(x-4)=56-35
7.(x-4)=21
x-4=21:7
x-4=3
x=3+4
x=7
Ủng hộ nha!
a) 580:(x-24)=329-150.21
b)7.(7-14)+35=25+279:9
a) 580 : ( x - 24 ) = 329 - 150 . 21
=> 580 : ( x - 24 ) = 329 - 150 . 2
=> 580 : ( x - 24 ) = 329 - 300
=> 580 : ( x - 24 ) = 29
=> x - 24 = 20
=> x = 20 + 24
=> x = 44
Vậy x = 44
mk nha các bạn !!!
=> 580 : ( x - 24 ) = 329 - 150 . 2
=> 580 : ( x - 24 ) = 329 - 300
=> 580 : ( x - 24 ) = 29
=> x - 24 = 20
=> x = 20 + 24
=> x = 44
Vậy x = 44
Tìm x
a, 580 :( x -24 ) =329 -150 : 2
b, 7 (x-1 ) +35= 25 + 279 :9
c,4 ( 2x+ 7 ) -3 (3x -2 ) =24
d,( x-1 ) (x-2) =3(x-1)
e,( x+ 3 ) + ( x+7 ) + ( x + 11 ) + ........+ ( x+ 79 ) =860
a, ĐK: \(x\ne24\)
580 :( x -24 ) =329 -150 : 2
<=> 580 :( x -24 ) = 329 - 75
<=> 580 :( x -24 ) = 254
<=> x - 24 = \(\frac{290}{127}\)
<=> x = \(\frac{3338}{127}\left(TM\right)\)
Vậy \(x=\frac{3338}{127}\)
b, 7 (x-1 ) +35= 25 + 279 :9
<=> 7x - 7 + 35 = 25 + 31
<=> 7x +28 = 56
<=> 7x = 28
<=> x = 4
Vậy x =4
c,4 ( 2x+ 7 ) -3 (3x -2 ) =24
<=> 8x + 28 - 9x + 6 = 24
<=> 34 - x = 24
<=> x = 10
Vậy x = 10
d,( x-1 ) (x-2) =3(x-1)
<=> ( x-1 ) (x-2) - 3(x-1) = 0
<=> (x- 1)(x - 2 - 3) = 0
<=> (x -1)(x - 5) = 0
<=> \(\left[{}\begin{matrix}x-1=0\\x-5=0\end{matrix}\right.\) <=> \(\left[{}\begin{matrix}x=1\\x=5\end{matrix}\right.\)
Vậy x ={1; 5}
e, (x + 3) + (x + 7) + (x + 11) + ... + (x + 79) = 860
x + 3 + x + 7 + x + 11 + ... + x + 79 = 860
Có tất cả: (79 - 3) : 4 + 1 = 20 số hạng \(\Rightarrow\) có 20x
hay x + 3 + x + 7 + x + 11 + ... + x + 79 = 860
\(\Rightarrow\) 20x + (3 + 7 + ... + 79) = 860
3 + 7 + ... + 79 = (79 + 3) x 20 : 2 = 820
\(\Rightarrow\) 20x + (3 + 7 + ... + 79) = 860
\(\Rightarrow\) 20x + 820 = 860
\(\Rightarrow\) 20x = 40
\(\Rightarrow\) x = 2
Vậy x = 2
Chúc bn học tốt!
Chứng minh rằng :
a) 817-279+329⋮⋮33
b) 109+108+107⋮⋮55
c)\dfrac{9^{11}-9^{10}-9^9}{639}\in N639911−910−99∈N
d)817-279-913⋮⋮45
Bài 1: Tìm x, biết:
a) 24 . x - 32 . x = 145 - 255 / 51
b) 580 / ( x - 24 ) = 329 - 150 . 2
c) 7. ( x - 14 ) + 35 = 25 + 279 / 9
thanks
a) \(2^4.x-3^2.x=145-\frac{255}{51}\Rightarrow x.\left(2^4-3^2\right)=145-5\)
\(\Rightarrow7.x=140\Rightarrow x=20\)
b) \(\frac{580}{x-24}=329-150.2\Rightarrow\frac{580}{x-24}=329-300\Rightarrow\frac{580}{x-24}=29\Rightarrow x-24=20\)
\(\Rightarrow x=44\)
c) \(7.\left(x-14\right)+35=25+\frac{279}{9}\Rightarrow7.\left(x-14\right)=25+31-35\)
\(\Rightarrow7.\left(x-14\right)=21\Rightarrow x-14=3\Rightarrow x=17\)
Bài 1: Tìm x
a) 7x + 2x = 918
b) 16 . x - 9 . x = 145 - 225 : 51
c) 3. ( x - 2 ) + 150 = 240
d) 580 : ( x - 24 ) = 329 - 150 . 2
e) 7. ( x - 14 ) + 35 = 25 + 279 : 9
g) [ ( 6 . x -72) : 2 - 8] . 28 = 5628
Chứng minh rằng:
a) 76 + 75 - 74 ⋮ 55
b) 817 - 279 + 329 ⋮ 33
a) 7⁶ + 7⁵ - 7⁴
= 7⁴.(7² + 7 - 1)
= 7⁴.55 ⋮ 55
Vậy (7⁶ + 7⁵ - 7⁴) ⋮ 55
b) 81⁷ - 27⁹ + 3²⁹
= (3⁴)⁷ - (3³)⁹ + 3²⁹
= 3²⁸ - 3²⁷ + 3²⁹
= 3²⁶.(3² - 3 + 3³)
= 3²⁶.(9 - 3 + 27)
= 3²⁶.33 ⋮ 33
Vậy (81⁷ - 27⁹ + 3²⁹) ⋮ 33
Tính nhanh:
c, C = 279 - (145 + 279) +145
d, D = - 479 - (2002 - 479) + (2002 - 18)
e, E = - (3251 - 243) + (3250 - 243)
f, F = -3752 - (29 - 3652) - 51
g, G = -329 + (15 - 101) - (25 - 440 -329)
Giúp mk nha mấy bn!!!
máy tính casio hân hạnh tài trợ :'>
Máy tính Casio hân hạnh tài trợ
\(c,\)\(C=279-\left(145+279\right)+145\)
\(C=279-145-279+145\)
\(C=\left(279-279\right)+\left(145-145\right)\)
\(C=0+0\)
\(C=0\)
Vậy C = 0
\(d,\)\(D=-479-\left(2002-479\right)+\left(2002-18\right)\)
\(D=-479-2002+479+2002-18\)
\(D=\left(-479+479\right)+\left(-2002+2002\right)-18\)
\(D=0+0-18\)
\(D=-18\)
Vậy D = -18
\(e,\)\(E=-\left(3251-243\right)+\left(3250-243\right)\)
\(E=-3251+243+3250-243\)
\(E=\left(-3251+3250\right)+\left(243-243\right)\)
\(E=-1+0\)
\(E=-1\)
Vậy E = -1
\(f,\)\(F=-3752-\left(29-3652\right)-51\)
\(F=-3752-29+3652-51\)
\(F=\left(-3752+3652\right)-\left(29+51\right)\)
\(F=-100-80\)
\(F=-180\)
Vậy F = -180
\(g,\)\(G=-329+\left(15-101\right)-\left(25-440-329\right)\)
\(G=-329+15-101-25+440+329\)
\(G=\left(-329+329\right)+\left(15-25\right)+\left(-101+440\right)\)
\(G=0-10+339\)
\(G=329\)
Vậy G = 329
Banh Bao Tong
Tìm x :
a)\(2^4.x-3^2.x=145-255:51\)
b)\(580:\left(x-24\right)=329-150.2^1\)
c)\(7.\left(x-14\right)+35=25+279:9\)
b)580:(x-24)=329-150.2 580:(x-24)=329-300 580:(x-24)=29 (x-24)=580:29 (x-24)=20 x=20+24 x=44
So sánh hai số:
a) -39 và - 54;
b) -3 179 và -3 279.
a) Vì 39 < 54 nên -39 > -54
b) Vì 3 179 < 3 279 nên - 3 179 > - 3 279.