64x+225=700-75-36x

=>64x+36x=700-75-225

=>64x+36x=400

=>100x=400

=>x=400:100

=>x=4

Vậy x=4 thỏa mãn yêu cầu đề bài

bài 2 

a] = 3 x \(\frac{4343}{7171}\)= \(\frac{17372}{7171}\)= \(\frac{172}{71}\)

b] = \(\frac{1}{33}\)x \(\frac{44}{7}\)= \(\frac{1}{3}\)x \(\frac{4}{7}\)=\(\frac{4}{21}\)

bài 1 

a] y là 9

b] <=> 64y + 36y = 700 - 75 - 225

<=> 100y = 400

<=> y = 4

trên lớp cô sửa rồi nên mình giải luôn:

1) Tìm y

a) y3 + 3y = 12 x 11

    y3 + 3y = 132

    y x 10 + 3 + 3 x 10 + y = 132

   ( y x 10 + y ) + ( 3 x 10 + 3 ) = 132

     11 x y + 33 = 132 

     11 x y = 132 - 33

     11 x y = 99

            y = 99 : 11

            y = 9

b) 64 x y + 225 = 700 - 75 - 36 x y

    64 x y + 225 = 625 - 36 x y

    64 x y + 36 x y = 625 -225

    64 x y + 36 x y = 400

    ( 64 + 36 ) x y = 400

    100 x y = 400

              y =  400 : 100

              y = 4

2) Tính

a) \(\frac{4343}{7171}+\frac{4343}{7171}+\frac{4343}{7171}+\frac{4343}{7171}\)

\(=\frac{4343}{7171}\times4\)

\(=\frac{43}{71}\times4\)

\(=\frac{172}{71}\)

b) A = \(\frac{1}{33}\times\left(\frac{33}{12}+\frac{3333}{2020}+\frac{333333}{303030}+\frac{33333333}{42424242}\right)\)

   Ta có:

   \(\frac{3333}{2020}=\frac{3333:101}{2020:101}=\frac{33}{20}\)

   \(\frac{333333}{303030}=\frac{333333:10101}{303030:10101}=\frac{33}{30}\)

  \(\frac{33333333}{42424242}=\frac{33333333:1010101}{42424242:1010101}=\frac{33}{42}\)

   A = \(\frac{1}{33}\times\left(\frac{33}{12}+\frac{33}{20}+\frac{33}{30}+\frac{33}{42}\right)\)

   A = \(\frac{1}{33}\times33\left(\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+\frac{1}{42}\right)\)

  A = 1 x \(\left(\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+\frac{1}{42}\right)\)

  A = 1 x \(\left(\frac{1}{3x4}+\frac{1}{4x5}+\frac{1}{5x6}+\frac{1}{6x7}\right)\)

  A = 1 x \(\left(\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+\frac{1}{5}-\frac{1}{6}+\frac{1}{6}-\frac{1}{7}\right)\)

  A = 1 x \(\left(\frac{1}{3}-\frac{1}{7}\right)\)

  A = 1 x \(\left(\frac{7}{21}-\frac{3}{21}\right)\)

  A = 1 x \(\frac{4}{21}\)

  A = \(\frac{4}{21}\)

dễ vãi lol ra bn ngu vãi đái

a, \(\left(x-y+4\right)^2-\left(2x+3y-1\right)^2=\left(x-y+4+2x+3y-1\right)\left(x-y+4-2x-3y+1\right)\)

\(=\left(3x+2y+3\right)\left(-x-4y+5\right)\)

b, \(x^6+y^6=\left(x^2\right)^3+\left(y^2\right)^3=\left(x^2+y^2\right)\left(x^4-x^2y^2+y^4\right)\)

c, \(x^{16}-1=\left(x^2\right)^8-1=\left[\left(x^2\right)^4\right]^2-1=\left(x^8-1\right)\left(x^8+1\right)\)

Phân tích à :)

a) ( x - y + 4 )² - ( 2x + 3y - 1 )²

= [ ( x - y + 4 ) - ( 2x + 3y - 1 ) ][ ( x - y + 4 ) + ( 2x + 3y - 1 ) ]

= ( x - y + 4 - 2x - 3y + 1 )( x - y + 4 + 2x + 3y - 1 )

= ( -x - 4y + 5 )( 3x + 2y + 3 )

b) x⁶ + y⁶ = ( x² )³ + ( y² )³ = ( x² + y² )( x⁴ - x²y² + y⁴ )

c) x¹⁶ - 1 = ( x⁸ )² - 1² = ( x⁸ - 1 )( x⁸ + 1 )

= ( x⁴ - 1 )( x⁴ + 1 )( x⁸ + 1 )

= ( x² - 1 )( x² + 1 )( x⁴ + 1 )( x⁸ + 1 )

= ( x - 1 )( x + 1 )( x² + 1 )( x⁴ + 1 )( x⁸ + 1 )

d) x³⁶ - 64 = ( x¹⁸ )² - 8²

= ( x¹⁸ - 8 )( x¹⁸ + 8 )

= ( x⁶ - 2 )( x¹² + 2x + 4 )( x⁶ + 2 )( x¹² - 2x + 4 )

e) 9x² + 90x + 225 - ( x - 7 )²

= ( 3x + 15 )² - ( x - 7 )²

= ( 3x + 15 - x + 7 )( 3x + 15 + x - 7 )

= ( 2x + 22 )( 2x - 8 )

= 2( x + 11 ).2( x - 4 )

= 4( x + 11 )( x - 4 )

f) 49( y - 4 )² - 9y² - 36y - 36

= 7²( y - 4 )² - ( 9y² + 36y + 36 )

= ( 7y - 28 )² - ( 3y + 6 )² 

= ( 7y - 28 - 3y - 6 )( 7y - 28 + 3y + 6 )

= ( 4y - 34 )( 10y - 22 )

= 2( 2y - 17 ).2( 5y - 11 )

= 4( 2y - 17 )( 5y - 11 )

A, 2 x 26 x 5 =( 5 x 2) x 26

10 x 26

=260                   

 b,4 x 37 x 25 =( 4 x 25) x 26

= 100 x 26

= 3700           

 c, 25 x 5 x 4 x 27 x 2 =( 25 x 4 ) x ( 2x 5) x 27

= 100 x 10 x 27 

= 1000x 27 

=27000

d,28 x 64 + 28 x 36 = 28 x ( 64 + 36 )

= 28 x 100

=2800

 e, 769 x 85 - 769 x 75  = 769 x ( 85 - 75 )

=769 x 10

=7690

f, 56 x 37 + 56 x 63 = 56 x ( 37 + 63 )

= 56 x 100

=5600

a. = 26 x (2 x 5)

   = 26 x 10 =260

b.=( 25x4) x37

   =100 x37=3700

c.=(25x4) x(5x2) x27

   =100 x10 x27

   = 27000

d.=28 x( 64+36)

   =28 x100

  = 2800

e.=769 x( 85-75)

    =769 x10 =7690

f. =56 x(37 +63)

  =56 x100

= 5600

a)364+225+436=(364+436)+225=800+225=1025

b)125x14x25x8x4=(125x8)x(25x4)x14=1000x100x14=100000x14=1400000

câu c bạn ra đề sai rồi để mk sửa lại rồi làm luôn.

sửa c) 36x49+64x49=(36+64)x49=100x49=4900

tk nha

\(364+225+436\)

\(=\left(364+436\right)+225\)

\(=800+225\)

\(=1025\)

a)(364+436)+225

=800+225

=1025

b)(125x8)x(25x4)x14

=1000x100x4

=400000

c)(49x64)x(36x49)

=3136+1764

=4900

=36x(28+82)+64x(69+41)

=36x110+64x110

=110x(26+64)

=110x100

=11000

**** bn hiền

36x28+36x82+64x69+64x41

=36x(28+82)+64x(69+41)

=36x110+64x110

=110x(36+64)

=110x100

=11000

36 x ( 28 + 82 ) + 64 x ( 69 + 41 ) = ( 36 + 64 ) x  (28 + 82)  = 100 x 110 = 11000

a: x-240:12=8

=>x-20=8

=>x=28

b: \(19+\dfrac{225}{6-x}=64\)

=>\(\dfrac{225}{6-x}=45\)

=>6-x=5

=>x=1

c: Đề thiếu rồi bạn

\(X-240:12=8\\ X-20=8\\ X=8+20=28\\ ---\\ 19+225:\left(6-X\right)=64\\ 225:\left(6-X\right)=64-19=45\\ 6-X=225:45=5\\ X=6-5=1\)

A.35 x 34 + 35 x 38 + 65 x 75 + 65 x 45

Câu này không tính hợp lí được

B. 12x 53 + 53 x 172 - 53 x 84

= 53 x (12 + 172 - 84)

= 53 x 100

= 5300

C. 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41

= 36 x (28+82) + 64 x (69+41)

= 36 x 110 + 64 x 110

= (36+64) x 110

= 100 x 110

= 11 000

D. A = 1+2+3+...+100

= (1+ 100) x 50

= 101 x 50

= 5050

E. B =17+19+...+101+103

= (103 +17) x [(103 - 17):2 + 1]

= 120 x 44

=5280

G. D= 3x (12+13+14+15) + 3x(8+7+6+5)

= 3 x (5+6+7+8+12+13+14+15)

= 3 x (20 x 4)

= 3 x 80

=240

a) 10320

b) 5300

c) 11000

d) 5050

e) 2460

g)  240