a.\(2.x+69.2=49.4\)

\(2.x+138=196\)

\(2x=58\)

\(x=29\)

Câu b xem lại đề nha,

c.\(25.\left(x-75\right)=25\)

\(\left(x-75\right)=1\)

\(x=76\)

d.\(165-\left(35:x+3\right).19=13\)

\(\left(35:x+3\right).19=152\)

\(\left(35:x+3\right)=8\)

\(35:x=5\)

\(x=7\)

câu h bài 2

4:2x=10

2x=4:10

2x=4/10

x=4/10:2

x=1/5

a)  2000.2000..>.. 1990.2010

b) 25.33 -10 ..<..31.26+10

d)32.53 -10 ..<..53.31+32

e) 1998.1998..>..1996.2000

  -Bài này không có ý c hả bạn?

1/2×(2×x-3)+105/2=-137/2

1/2×(2×x-3)=-137/2-105/2

1/2×(2×x-3)=-242/2

2×x-3=-242/2:1/2

2×x-3=-242

2.x=(-242)+3

2.x=239

x=239:2

x=239/2

A,-12×25-25×75-25×13

=[(-12)-75-13].25

=(-100).25

-2500

B,-50/7×49/10-35/2×-10/7+ -25/3× -9/5

=(-35)-(-25)+(-13)

=-23

C,-354+265-156+125

=[(-354)-156]+(265+125)

=(-510)+277

=-233

D,-74+40-50+16-35

=(-74)+40+(-50)+16+(-35)

=[(-74)+(-35)]+[40+(-50)+16]

=(-109)+26

=-83

E,-2/3×4/5+-4/5×4/3-0,125

=-2/3.4/5+4/5.(-4/3)-0,125

=4/5.[-2/3+(-4/3)]-0,125

=4/5.(-2)-0,125

=-8/5-0,125

=(-1,6)+(-0,125)

=-1,725

-2/3×4/5+ -4/5×4/3-0,125

Giúp e nốt ik ạ

a) \(215+x=400\)

\(\Rightarrow x=400-215\)

\(\Rightarrow x=185\)

b) \(12,5-2x=\dfrac{1}{5}\)

\(\Rightarrow2x=12,5-\dfrac{1}{5}\)

\(\Rightarrow2x=\dfrac{123}{10}\)

\(\Rightarrow x=\dfrac{123}{10}:2\)

\(\Rightarrow x=\dfrac{123}{20}\)

còn câu c d nhanh cậu ơi

a) 12 : x + 5 = 33 

     12 : x       = 33 - 5

     12 : x        = 28

             x       = 12 : 28

             x        = 1/4

Vậy x = 1/4

b) 5*(x + 19) = 170 - 50

5*(x+19) = 120

 x + 19 = 120 : 5

x + 19 = 24 

 x = 24 - 19

x = 5

Vậy x = 5

c) 11*(x - 6) - 11 = 4*x

11*(x-7) = 4x

11x - 77 = 4x

11x - 4x = 77

7x = 77

x = 11

Vậy x = 11 

Theo mình kết quả là

a, X là 4     b, X = 4    c, X = 5    d, X = 3    e, X = 16

Đúng thì k nhé . 

THANKS

a) x=4

b) x=4

c) x=4

d) x=-11

e) x=26

`a)4/5:3/x xx2/11=24/165`

`(4/5xx2/11)xx 3/x=8/55`

`8/55xx3/x=8/55`

`3/x=8/55:8/55`

`3/x=1`

`3:x=1`

`x=3:1`

`x=3`

____________________________________________

`b)4/3:x/5=5/13xx4/9`

`4/3:x/5=20/117`

`x/5=4/3:20/117`

`x/5=39/5`

`x=39`

A) 4/5:3/x X 2/11=24/165

\(\dfrac{4}{5}:\dfrac{3}{x}X\dfrac{2}{11}=\dfrac{24}{165}\)

\(\dfrac{3}{x}=\dfrac{24}{165}:\dfrac{4}{5}:\dfrac{2}{11}\)

\(\dfrac{3}{x}=1\)

\(\dfrac{3}{x}=\dfrac{3}{3}\)

=> x=3

B) \(\dfrac{4}{3}:\dfrac{x}{5}=\dfrac{5}{13}x\dfrac{4}{9}\)

\(\dfrac{4}{3}:\dfrac{x}{5}=\dfrac{20}{117}\)

\(\dfrac{x}{5}=\dfrac{4}{3}:\dfrac{20}{117}\)

\(\dfrac{x}{5}=\dfrac{39}{5}\)

=> x = 39

12 phần 25 trừ cho 14 phần 5 bằng bao nhiêu

a,\(\frac{37.13-13}{24+37.12}=\frac{36.13}{39.12}=1\)

b,125.7.16.25.4=(125.16).(25.4).7=2000.100.7=1400000

c,8.9.14+6.17.12+19.4.18=2^3.3^2.2.7+2.3.17.2^2.3+19.2^2.3^2.2=2^3.3^2.(2.7+17+19)=72.50=3600