a) (2 + x) : 5 = 6

2 + x = 6 $\times$ 5

2 + x = 30

x = 30 - 2

x = 28

b) 2 + x : 5 = 6

x : 5 = 6 - 2

x : 5 = 4

x = 4 $\times$ 5

x = 20

c) 2x - 3 = 11

2x = 11 + 3

2x = 14

x = 14 : 2

x = 7

d) 3 . (x - 18) + 75 = 0

3 . (x - 18) = -75

x - 18 = -75 : 3

x - 18 = -25

x = -25 + 18

x = -7

\(\left(x:23+45\right).67=8911\)

\(x:23+45=8911:67\)

\(x:23+45=133\)

\(x :23=133-45\)

\(x:23=88\)

\(x=88.23\)

\(x=2024\)

thiếu đề b1
 

Bài 2: 

a, \(\frac{44.52.60}{11.13.15}=\frac{4.11.4.13.4.15}{11.13.15}=4.4.4=64\)

b, \(123.456-456.123123=456\left(123-123123\right)=456.\left(-123000\right)=-56088000\)

Ta có :

456x36+456x61+4 x456+456

=456x(36+61+4+456)

=456x...tự tính

=...tự tính

Umm mình tưởng là cái 456 đó tính là 1 thôi chứ nhỉ ban???

\(456\times36+456\times61+4\times456+456\)

\(=456\times\left(36+61+4+1\right)\)

\(=456\times102\)

\(=45612\)

Học tốt

Em xem lại đề nhé !

\(\left\{{}\begin{matrix}P=E\\P+N+E=40\\P+E=22\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}P=E=11\\N=18\end{matrix}\right.\)

=> Chọn C

C

b: \(4m^2n-8m^2n-12n\)

\(=-4m^2n-12n\)

\(=-4n\left(m^2+3\right)\)

c: \(a^4-b^4=\left(a^2-b^2\right)\left(a^2+b^2\right)=\left(a^2+b^2\right)\left(a-b\right)\left(a+b\right)\)

d: \(16b^4-9c^2\)

\(=\left(4b^2-3c\right)\left(4b^2+3c\right)\)

e: \(5a\left(x+y\right)+x+y=\left(x+y\right)\left(5a+1\right)\)

a, 37 052 + 28 456

b, 596 178 – 44 695

c, 487 x 215

d, 14790 : 34

2010 x 2010 - 2009 x 2011

= ( 2011 - 2010 ) x 2010 - 2009 x 2011

= 2011 x 2010 - 1 x 2010 - 2009 x 2011

= 2011 x ( 2010 - 2009 ) - 1 x 2010

= 2011 x 1 - 2010 

= 2011 - 2010 

= 1

( 456 x 11 + 912 ) x 37 : ( 13 x 74 )

= ( 456 x 11 + 456 x 2 ) x 37 : ( 13 x 74 )

= [ 456 x ( 11 + 2 ) ] x 37 : ( 13 x 74 )

= [ 456 x 13 ] x 37 : ( 13 x 74 )

= 13 x 456 x 37 : ( 13 x 37 x 2 )

= 13 x 37 x 2 x 228 : ( 13 x 37 x 2 )

= ( 13 x 37 x 2 ) x 228 : ( 13 x 37 x 2 )

= ( 13 x 37 x 2 ) : ( 13 x 37 x 2 ) x 228

= 1 x 228

= 228

(44 x 52 x 60) : (11 x13 x 15 )

= [ ( 4 x 11 ) x ( 4 x 13 ) x ( 4 x 15 ) ] : (11 x13 x 15 )

= [ 4 x 11 x 4 x 13 x 4 x 15 ] : (11 x13 x 15 )

= [ ( 4 x 4 x 4 ) x ( 11 x 13 x 15 ) ] : (11 x13 x 15 )

= 64 x (11 x13 x 15 ) : (11 x13 x 15 )

= 64 x 1

= 64

a) 2010 x 2010 - 2009 x 2011 

= 2010 x 2010 - [ 2009 x ( 2010 +1) ]

=2010 x 2010 - 2009 x 2010 - 2009 

=2010( 2010 - 2009 ) -2009 

= 2010 -2019

= 1

c) ( 44 x 52 x60 ) : (11x13x15)

\(\frac{44\cdot52\cdot60}{11\cdot13\cdot15}=\frac{4\cdot11\cdot4\cdot13\cdot4\cdot15}{11\cdot13\cdot15}=64\)

B) (456 x 11 +912) x 37 : ( 13 x 74 )

= \(\frac{\left(456\cdot11+912\right)\cdot37}{13\cdot74}=\frac{\left[456\left(11+2\right)\right]\cdot37}{13\cdot37}=\frac{456\cdot13}{13\cdot2}=\frac{456}{2}=228\)

Nhớ k mik nha bn

a)(44x52x60):(11x13x15)                                                                                                                                    =(44:11)x(52:13)x(60:15)=4x4x4      =64      

\(a.\)

\(\left(44.52.60\right):\left(11.13.15\right)=\frac{44.52.60}{11.13.15}\frac{4.4.4\left(11.13.15\right)}{\left(11.13.15\right)}=4^3=64\)

b)=56144088-56144088=0            

\(a,x\left(y-2\right)=8\\ \Rightarrow x;\left(y-2\right)\inƯ\left(8\right)=\left\{-8;-4;-2;-1;1;2;4;8\right\}\)

Vậy \(\left(x;y\right)=\left(-8;1\right),\left(-4;0\right),\left(-2;-2\right),\left(-1;-6\right),\left(2;6\right),\left(4;4\right),\left(8;3\right)\)

\(b,\left(x-1\right)\left(y-2\right)=9\\ \Rightarrow\left(x-1\right),\left(y-2\right)\inƯ\left(9\right)=\left\{-9;-3;-1;1;3;9\right\}\)

Vậy \(\left(x;y\right)=\left(-8;1\right),\left(-2;-1\right),\left(0;-7\right),\left(2;11\right),\left(4;5\right),\left(10;3\right)\)

\(c,\left(x+1\right)\left(y-2\right)=15\\ \Rightarrow\left(x+1\right),\left(y-2\right)\inƯ\left(15\right)=\left\{-15;-1;1;15\right\}\)

Vậy \(\left(x;y\right)=\left(-16;1\right),\left(-2;-13\right),\left(0;17\right),\left(14;3\right)\)