\(\frac{5}{7}+\frac{3}{4}=\frac{41}{28}\)\(Đ\)

\(3+\frac{2}{5}=1\)\(S\)

\(\frac{11}{9}-\frac{5}{6}=\frac{7}{18}\)\(Đ\)

\(4-\frac{3}{7}=\frac{25}{7}\)\(Đ\)

\(x+\frac{4}{11}=\frac{3}{5}\).

          \(x=\frac{3}{5}-\frac{4}{11}\)

          \(x=\frac{13}{55}\)

Vậy ta chọn câu C

dung hay sai

5/7 + 3/4 = 41/28 .....Đ...

3 + 2/5 = 1....S....

11/9 - 5/6 = 7/18....Đ...

4 - 3/7 = 25/7.....

tim x

x + 4/11 =3/5

Đáp án : C .13/55

Bài Đúng hay Sai :

5/7 + 3/4 = 41/28 là đúng 

3 + 2/5 = 1 là sai 

11/9 - 5/6 = 7/18 là đúng 

4 - 3/7 = 25/7 là đúng 

Bài tìm x :

x + 4/11 = 3/5 

           x  = 3/5 - 4/11 

           x  = 13/55 

Vậy chọn đáp án C .

~ Chúc em học giỏi ! ~

A) \(y=5X-\frac{18.2}{18}=135X-2=13x=3\)

B)\(y=\frac{5x-36}{18}=13\frac{5x}{18}-2=13\frac{5x}{18}=15\frac{x}{18}=3x=54\)

sai bet te be nhe

a, 5x-36:18=13

5x-2=13

x=5-2

x=3

b,(5x-36):18=13

5x-36=13x18

5x-36=234

5x=234+36

5x=270

x=270:5

x=54

cho mình nhé:):):):):):):)@@@@@@@#######

| x + 13 | - 13 = 25 - 32

| x + 13 | = -7 + 13

| x + 13 | = 6

TH1:x + 13 = 6

=> x = -7

TH2:x + 13 = -6

=> x = -19

Ta có

\(5^x.5^{x+1}.5^{x+2}\le10^{18}:2^{18}=>5^{3x+3}\le5^{18}=>3x+3\le18=>x\le5\)

Tìm x

( 5x - 36 ) : 18 = 13

=> 5x - 36 = 234

=> 5x = 234 + 36

=> 5x = 270

=> x = 270 : 5

=> x = 54

\(\left(5x-36\right):18=13\)

\(5x-36=13.18\)

\(5x-36=234\)

\(5x=234+36\)

\(5x=270\)

\(x=\frac{270}{5}\)

\(x=54\)

(5x - 36) : 18 = 13

5x - 36 = 13.18

5x - 36 = 234

5x = 234 + 36

5x = 270

x = 270 : 5

x = 54

Vậy x = 54

Chúc bạn học tốt!

Tìm x thuoc z:

1) \(26-\left|x+9\right|=-13\)

\(\Leftrightarrow\left|x+9\right|=26-\left(-13\right)\)

\(\Leftrightarrow\left|x+9\right|=39\)

\(\Leftrightarrow\left[{}\begin{matrix}x+9=39\\x+9=-39\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=39-9=30\\x=-39-9=-48\end{matrix}\right.\)

Vậy: \(x\in\left\{30;-48\right\}\)

2) \(\left|x+7\right|-13=25\)

\(\Leftrightarrow\left|x+7\right|=25+13=38\)

\(\Leftrightarrow x+7\in\left\{38;-38\right\}\)

\(\Leftrightarrow x\in\left\{31;-45\right\}\)

Vậy:.................

tim x biet

\(1)123-3.\left(x+4\right)=23\)

\(\Leftrightarrow3\left(x+4\right)=123-23\)

\(\Leftrightarrow3\left(x+4\right)=100\)

\(\Leftrightarrow x+4=\frac{100}{3}\)

\(\Leftrightarrow x=\frac{100}{3}-4=\frac{100-12}{3}=\frac{88}{3}\)

Vậy:................

2) Tương tự

a)15/8+3/4-5/12

=45+18-10/24

=53/24

b)11/24.12/33+5/6

=11.12/12.2.11.3+5/6

=1/6+5/6

=6/6=1

c)15/8+7/24:5/8

=15/8+7/24.8/5

=15/8+7.8/3.8.5

=15/8+7/15

=đề sai, nếu đúng thì như này

=8/15+7/15

=15/15=1

hbhvgvvggvgbhhgvbnj

\(5^x.5^{x+1}.5^{x+2}=10....0:2^{18}\Rightarrow100..0:2^{18}=5^{18}.2^{18}:2^{18}=5^{18}\)

\(5^x.5^{x+1}.5^{x+2}\Rightarrow x+x+1+x+2=5^{18}\)

\(\Rightarrow3x+3=18\)

\(\Rightarrow3x=15\)

\(\Rightarrow x=5\)

Vậy x = 5