bạn nhập rõ hơn đi

4(4,5-2x)=7

18-8x=7

X=11/8

deo hieu

a) 2/3 x = 2/9 + 4/9

=> 2/3 x = 2/3

=> x = 1

b) 4,5 - 2x = 11/14 + \(-1\frac{4}{7}\)

=> 4,5 - 2x = 5/14

=> 2x = 4,5 - 5/14

=> 2x = 29/7

=> x= 29/14

4,5-2x=11/4:11/7

4,5 - 2x= 7/4

2x=9/2 - 7/4

2x= 18/4-7/4

2x=11/4

x=11/4:2

x=11/8 

\(\left(4,5-2x\right).1\dfrac{4}{7}+\dfrac{11}{14}\) 

\(=\dfrac{99}{14}-\dfrac{22}{7}x+\dfrac{11}{14}\) 

\(=\left(\dfrac{99}{14}+\dfrac{11}{14}\right)-\dfrac{22}{7}x\) 

\(=\dfrac{55}{7}-\dfrac{22}{7}x\) 
\(=\dfrac{33}{7}+\dfrac{22}{7}.\left(1-x\right)\)

Câu 1:

\(=\dfrac{21}{31}+\dfrac{1}{3}-\dfrac{44}{53}+\dfrac{10}{31}-\dfrac{9}{53}=\dfrac{1}{3}\)

Câu 2:

1: =>1,3x=-1,31

=>130x=-131

=>x=-131/130

2: =>(4,5-2x)=11/14:(-11/7)=-7/14=-1/2=-0,5

=>2x=5

=>x=5/2

(4,5-2x) * -2=11/14

9/2-2x=11/14:-2

9/2-2x=-11/28

2x=9/2 - (-11/28)

2x=137/28

x=137/28:2

x=137/56

(4,5-2x) * -2=11/14

9/2-2x=11/14:-2

9/2-2x=-11/28

2x=9/2 - (-11/28)

2x=137/28

x=137/28:2

x=137/56

=127/56 nha bn

(4,5-2x) * -2=11/14

9/2-2x=11/14:-2

9/2-2x=-11/28

2x=9/2 - (-11/28)

2x=137/28

x=137/28:2

x=137/56

 NHA BAN 

(4,5-2x) * -2=11/14

9/2-2x=11/14:-2

9/2-2x=-11/28

2x=9/2 - (-11/28)

2x=137/28

x=137/28:2

x=137/56

(4,5-2x) * -2=11/14

9/2-2x=11/14:-2

9/2-2x=-11/28

2x=9/2 - (-11/28)

2x=137/28

x=137/28:2

x=137/56

Theo bài ra, ta có:

\(\left(4,5-2x\right).1\dfrac{4}{7}=\dfrac{11}{14}\\ \left(4,5-2x\right).\dfrac{11}{7}=\dfrac{11}{14}\\ 4,5-2x=\dfrac{11}{14}:\dfrac{11}{7}\\ 4,5-2x=\dfrac{1}{2}\\ 2x=4,5-\dfrac{1}{2}\\ \Rightarrow2x=4\\ \Rightarrow x=2\)

Vậy x = 2

\(\left(4,5-2x\right).1\dfrac{4}{7}=\dfrac{11}{14}\)

\(\Leftrightarrow\left(4,5-2x\right).\dfrac{11}{7}=\dfrac{11}{14}\)

\(\Leftrightarrow4,5-2x=\dfrac{11}{14}:\dfrac{11}{7}\)

\(\Leftrightarrow4,5-2x=\dfrac{11}{14}.\dfrac{7}{11}\)

\(\Leftrightarrow4,5-2x=\dfrac{1}{2}\)

\(\Leftrightarrow-2x=\dfrac{1}{2}-4,5\)

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

\(\Leftrightarrow x=2\)

Vậy phương trình có ngiệm x = 2 .