1)

\(\frac{3}{4}.x+\frac{x}{5}=\frac{1}{6}\)

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

\(x.\frac{19}{20}=\frac{1}{6}\)

\(x=\frac{1}{6}:\frac{19}{20}\)

\(x=\frac{10}{57}\)

2) 

\(x+3\frac{1}{2}+x=24\frac{1}{4}\)

\(2x+3\frac{1}{2}=24\frac{1}{4}\)

\(2x=24\frac{1}{4}-3\frac{1}{2}\)

\(2x=\frac{83}{4}\)

\(x=\frac{83}{4}:2\)

\(x=\frac{83}{8}\)

64 .  4^x = 16⁸

4³ . 4^x = 4¹⁶

4^3+x = 4¹⁶

3 + x = 16

x = 16 - 3

x = 13

a) 3⁴. 6-5.[ 131 - ( 15 . 9)² ] : 5² . 5

  =81.6-5.[ 131 - 135² ] : 25.5

  =486 - 5 . [ 131 - 18225 ] : 25 .5

  = 486 - 5 . ( -18094 ) : 25 . 5

  =486 - ( -90470) : 25 . 5

  =486 + 18094

  =18580

b) 28. { 420 : 6 + [ 150 - ( 68 . 2 - 2³ . 5)]}

  =28. { 70 + [ 150 - ( 136 - 8. 5 )]}

  =28. { 70 + [ 150 - ( 136 - 40 )]}

  =28.{ 70 + [ 150 - 96 ]}

  =28.{70 + 54}

  =28.124

  =3472

a,=18580 

b, =3472

x = 100 : 10

x = 10

10x = 100

    x = 100 : 10

    x = 10

Ai tk mk mk tk lại

12 . 2 = 24

~ Ủng hộ nhé anh chị em ~

\(12x2=24\)

mk nghỉ x=4

tk cho mk nha

=> x(x-4)=0

=>x=4 hoac x=0

Đặt \(A=\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{90}\)

\(A=\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{9.10}\)

\(A=\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{9}-\frac{1}{10}\)

\(A=\frac{1}{2}-\frac{1}{10}\)

\(A=\frac{2}{5}\)

\(\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{90}\)

\(=\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{9.10}\)

\(=\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{9}-\frac{1}{10}\)

\(=\frac{1}{2}-\frac{1}{10}+0+0+...+0\)

\(=\frac{2}{5}\)

~ Ủng hộ nhé anh chị em ~

B = 3( 2x - 1 ) + | x- 5 |

B = 6x - 3 + | x + 5 |

Mấy phần kia bạn thay vào rồi tính nhé

~ Ủng hộ nhé anh chị em ~

Bonking bạn giải ra cho rõ ràng đc ko!