a, 190 - 2(2x-6) = 182

=> 2 ( 2x - 6 ) = 8

=> 2x - 6 = 4

=> 2x = 10

=> x = 5

b, 1300 : [ 120 - ( x - 9 ) ] = 25

=> [ 120 -(  x -  9 )  ] = 52

=> x - 9 = 68

=> x = 77

c, 1793 ( x : 1792 ) = 0

=> x : 1972 = 0

=> x = 0

a)

190-2(2x-6)=182

2(2x-6)=190-182

2(2x-6)=8

2x-6=8:2

2x-6=4

2x=4-6

2x=-2

x=-2:2

x=-1

\(190-2\left(2x-6\right)=182\)

\(2\left(2x-6\right)=190-182=8\)

\(2x-6=8:2=4\)

\(2x=6-4=2\)

\(\Rightarrow x=2:2=1\)

Vậy \(x=1\)

a) y x 5 = 1948 + 247

y x 5 = 2195

y = 2195 : 5

y = 439

b) y : 3 = 190 - 90

y : 3 = 100

y = 100 x 3

y = 300

c) y - 8357 = 3829 x 2

y - 8357 = 7658

y = 7658 + 8357

y = 16 015

d) y x 8 = 182 x 4

y x 8 = 728

y = 728 : 8

y = 91

a) y x 5 = 1948 + 247

y x 5 = 2195

y = 2195 :5

y = 439

b) y : 3 = 190 - 90

y : 3 = 100

y = 100 x 3

y = 300

c) y - 8357 = 3829 x 2

y - 8357 = 7658

y = 7658 + 8357

y = 16015

d) y x 8 = 182 x 4

y x 8 = 728

y = 728 : 8

y = 91

a) y x 5 = 1948 + 247

y x 5 = 2195

y = 2195 : 5

y = 439

b) y : 3 = 190 - 90

y : 3 = 100

y = 100 x 3

y = 300

c) y - 8357 = 3829 x 2

y - 8357 = 7658

y = 7658 + 8357

y = 16 015

d) y x 8 = 182 x 4

y x 8 = 728

y = 728 : 8

y = 91

\(\dfrac{2}{4\times6}+\dfrac{2}{6\times8}+...+\dfrac{2}{188\times190}\\ =\dfrac{1}{4}-\dfrac{1}{6}+\dfrac{1}{6}-\dfrac{1}{8}+....+\dfrac{1}{188}-\dfrac{1}{190}\\ =\dfrac{1}{4}-\dfrac{1}{190}\\ =\dfrac{93}{380}\)

\(\dfrac{2}{4\times6}+\dfrac{2}{6\times8}+...+\dfrac{2}{188\times190}\)

\(=\dfrac{1}{4}-\dfrac{1}{6}+\dfrac{1}{6}-\dfrac{1}{8}+...+\dfrac{1}{188}-\dfrac{1}{190}\)

\(=\dfrac{1}{4}-\dfrac{1}{190}\)

\(=\dfrac{190-4}{760}\)

\(=\dfrac{186}{760}=\dfrac{93}{380}\)

(2+4+6+...+2020) x (182 x 234 -91 x 468)

= (2+4+6+...+2020) x (91x2x234 -91 x 234x2)

= (2+4+6+...+2020) x 0

=0

<=> 1+2+3+...+x=91
<=> x(x+1)/2=91
<=>x²+x-182=0
<=> x=13 hoặc x=-14(loại)
Vậy x=13

Gì đây em?? Xem đúng chưa hả?

Nếu hỏi vậy thì đúng rồi nhé.

Dạ cảm ơn anh

30.(x+2)-6.(x-5)+x=190

=>30x+60-6x+30+x=190

=>30x-6x+x=190-60-30

=>25x=100

=>x=100:25

=>x=4

x=40

cần lời giải thì pm