a)        \(\left(\frac{2x}{3}-3\right):\left(-10\right)=\frac{2}{5}\)

   <=>   \(\frac{2x}{3}-3=\frac{2}{5}.\left(-10\right)\)

   <=>   \(\frac{2x}{3}-3=-4\)

   <=>    \(\frac{2x}{3}=-4+3=-1\)

   <=>     \(2x=-1.3=-3\)

   <=> \(x=\frac{-3}{2}\)

Vậy \(x=\frac{-3}{2}\)

b) \(1,5x-2\frac{1}{3}x=1,5-\frac{2}{3}\)

\(x.\left(1,5-2\frac{1}{3}\right)=\frac{5}{6}\)

\(x.\left(\frac{-5}{6}\right)=\frac{5}{6}\)

\(x=\frac{5}{6}:\left(\frac{-5}{6}\right)=\frac{5}{6}.\left(\frac{-6}{5}\right)=-1\)

Vậy \(x=-1\)

Nếu đúng thì cho mình nhé, chúc bạn học tốt !

a. \(0,5x-\frac{1}{3}x=\frac{1}{3}\)

 \(\left(0,5-\frac{1}{3}\right)x=\frac{1}{3}\)

                   \(\frac{1}{6}x=\frac{1}{3}\)

                         \(x=\frac{1}{3}:\frac{1}{6}\)

                        \(x=2\)

b. \(x:3\frac{1}{2}=-1,5\)

           \(x=-1,5\times3\frac{1}{2}\)

           \(x=-5,25\)

c. \(1,5x=\frac{11}{5}\)

          \(x=\frac{22}{15}\)

A. 0,5x - 1/3x = 1/3

    (0,5 - 1/3)x = 1/3

              1/6x = 1/3

                  x = 2

B. x : 3 1/2 = -1,5

              x = -1,5 x 3 1/2

              x = -5,25

C. 1,5x = 11/5

        x = 22/15

\(a,\)\(2x+3>5\)

\(\Rightarrow2x>5-3\)

\(\Rightarrow2x>2\)

\(\Rightarrow x>1\)

\(\frac{3}{5}x+\frac{12}{15}< 0\)

\(\Rightarrow\frac{3}{5}x+\frac{4}{5}< 0\)

\(\Rightarrow3x+4< 0\)

\(\Rightarrow3x< -4\)

\(\Rightarrow x>\frac{-4}{3}\)

Đây là những bài cơ bản mà bạn!

bạn ấy muốn thách xem bạn nào đủ kiên nhẫn đánh hết chỗ này

a) Ta có: \(\frac{7}{8}x-5\left(x-9\right)=\frac{20x+1,5}{6}\)

\(\Leftrightarrow\frac{7x}{8}-5x+45-\frac{20x+1,5}{6}=0\)

\(\Leftrightarrow\frac{21x}{24}-\frac{120x}{24}+\frac{1080}{24}-\frac{4\left(20x+1,5\right)}{24}=0\)

\(\Leftrightarrow-99x+1080-4\left(20x+1,5\right)=0\)

\(\Leftrightarrow-99x+1080-80x-6=0\)

\(\Leftrightarrow1074-179x=0\)

\(\Leftrightarrow179x=1074\)

hay x=6

Vậy: x=6

b) Ta có: \(4\left(0,5-1,5x\right)=-\frac{5x-6}{3}\)

\(\Leftrightarrow2-6x=\frac{6-5x}{3}\)

\(\Leftrightarrow\frac{3\left(2-6x\right)}{3}-\frac{6-5x}{3}=0\)

\(\Leftrightarrow6-18x-6+5x=0\)

\(\Leftrightarrow-13x=0\)

mà -13≠0

nên x=0

Vậy: x=0

c) Ta có: \(\frac{x+4}{5}-x+4=\frac{x}{3}-\frac{x-2}{2}\)

\(\Leftrightarrow\frac{6\left(x+4\right)}{30}+\frac{30\left(-x+4\right)}{30}-\frac{10x}{30}+\frac{15\left(x-2\right)}{30}=0\)

\(\Leftrightarrow6\left(x+4\right)+30\left(4-x\right)-10x+15\left(x-2\right)=0\)

\(\Leftrightarrow6x+24+120-30x-10x+15x-30=0\)

\(\Leftrightarrow-19x+114=0\)

\(\Leftrightarrow-19x=-114\)

hay x=6

Vậy: x=6

d) Ta có: \(\frac{4x+3}{5}-\frac{6x-2}{7}=\frac{5x+4}{3}+3\)

\(\Leftrightarrow\frac{21\left(4x+3\right)}{105}-\frac{15\left(6x-2\right)}{105}-\frac{35\left(5x+4\right)}{105}-\frac{315}{105}=0\)

\(\Leftrightarrow84x+63-90x+30-175x-140-315=0\)

\(\Leftrightarrow-181x-362=0\)

\(\Leftrightarrow-181x=362\)

hay x=-2

Vậy: x=-2

e) Ta có: \(\frac{1}{4}\left(x+3\right)=3-\frac{1}{2}\left(x+1\right)-\frac{1}{3}\left(x+2\right)\)

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

\(\Leftrightarrow\frac{3\left(x+3\right)}{12}-\frac{36}{12}+\frac{6\left(x+1\right)}{12}+\frac{4\left(x+2\right)}{12}=0\)

\(\Leftrightarrow3x+9-36+6x+6+4x+8=0\)

\(\Leftrightarrow13x-13=0\)

\(\Leftrightarrow13x=13\)

hay x=1

Vậy: x=1

Câu a:

(1/5 - 3/4).x - 1,52 = - 0,48

(4/20 - 15/20)x = -0,48 + 1,52

- 11/20x = 1,04

x = 1,04 : (-11/20)

x = - 104/55

Vậy x = - 104/55

Câu b:

|x - 2| - 1,5x = 3/4 + 5/4x -25/7

|x -2| = 5/4x + 1,5x + 3/4

|x -2| = 1,25x + 1,5x + 0,75

|x -2| = 2,75x + 0,75

|x -2| ≥ 0 ∀ x

⇒ 2,75x + 0,75 ≥ 0

2,75x ≥ - 0,75

x ≥ - 0,75 : 2,75

x ≥ -3/11

Với x ≥ -3/11 ta có:

|x - 2| = 2,75x + 0,75

x - 2 = 2,75x + 0,75 hoặc x - 2 = - 2,75x - 0,75

Th1:

x - 2 = 2,75x + 0,75

2,75x - x = - 2 - 0,75

1,75x = - 2,75

x = -2,75 : 1,75

x = - 11/7 < -3/7 (tm)

Th2:

x - 2 = - 2,75x - 0,75

x + 2,75x = 2 - 0,75

3,75x = 1,25

x = 1,75 : 3,75

x = 1/3 (ktm)

Vậy x = -11/7

Mấy câu như vậy bạn tải photomath về dùng nhé :)