Câu 1 : ( 5x - 17 )³ = 27

           ( 5x - 17 )³ = 3³

     =>    5x - 17 = 3

            5x        = 3 + 17

            5x        =   20

             x         = 20 : 5

            x          =    4

cà khịa time x=+
 

cân cặc

1) \(\frac{17}{6}-\left(x-\frac{7}{6}\right)=\frac{7}{4}\)

\(\Rightarrow x-\frac{7}{6}=\frac{17}{6}-\frac{7}{4}\)

\(\Rightarrow x=\frac{13}{12}+\frac{7}{6}=\frac{9}{4}\)

2) \(\frac{3}{35}-\left(\frac{3}{5}-x\right)=\frac{2}{7}\)

\(\Rightarrow\)\(\frac{3}{5}-x=\frac{3}{35}-\frac{2}{7}=-\frac{1}{5}\)

\(\Rightarrow x=\frac{3}{5}-\left(-\frac{1}{5}\right)=\frac{4}{5}\)

3) 4) Hjhj^_^^_^

a. -3/4 x 12/-5 x (-25/6)=-15/2

b. -2 x -38/21 x -7/4 x (-3/8)=-19/8

c. (11/12: 33/16) x 3/5=4/15

d. 7/23 x [(-8/6)- 45/18]=-7/6

a. -3/4 x 12/-5 x (-25/6)=-15/2

b. -2 x -38/21 x -7/4 x (-3/8)=-19/8

c. (11/12: 33/16) x 3/5=4/15

d. 7/23 x [(-8/6)- 45/18]=-7/6

a)\(-\frac{6}{7}< \frac{3}{7}< \frac{18}{7}\)

b) \(\frac{17}{35}>\frac{17}{53}\)

c) \(\frac{17}{35}< \frac{17}{-35}\)

d) Ta có : \(\frac{12}{7}=\frac{60}{35}\)

                  \(\frac{17}{5}=\frac{85}{35}\)

          \(\Rightarrow\frac{12}{7}< \frac{17}{5}\)

a)\(\frac{3}{7}\)>\(\frac{18}{7}\)>\(\frac{-6}{7}\)

b)\(\frac{17}{35}\)>\(\frac{17}{53}\)

c)\(\frac{17}{35}\)<\(\frac{17}{-35}\)

d)\(\frac{12}{7}\)<\(\frac{17}{5}\)

hok tốt

Bài 1: 

a) Ta có: \(\dfrac{17}{6}-x\left(x-\dfrac{7}{6}\right)=\dfrac{7}{4}\)

\(\Leftrightarrow\dfrac{17}{6}-x^2+\dfrac{7}{6}x-\dfrac{7}{4}=0\)

\(\Leftrightarrow-x^2+\dfrac{7}{6}x+\dfrac{13}{12}=0\)

\(\Leftrightarrow-12x^2+14x+13=0\)

\(\Delta=14^2-4\cdot\left(-12\right)\cdot13=196+624=820\)

Vì Δ>0 nên phương trình có hai nghiệm phân biệt là:

\(\left\{{}\begin{matrix}x_1=\dfrac{14-2\sqrt{205}}{-24}=\dfrac{-7+\sqrt{205}}{12}\\x_2=\dfrac{14+2\sqrt{2015}}{-24}=\dfrac{-7-\sqrt{205}}{12}\end{matrix}\right.\)

b) Ta có: \(\dfrac{3}{35}-\left(\dfrac{3}{5}-x\right)=\dfrac{2}{7}\)

\(\Leftrightarrow\dfrac{3}{5}-x=\dfrac{3}{35}-\dfrac{10}{35}=\dfrac{-7}{35}=\dfrac{-1}{5}\)

hay \(x=\dfrac{3}{5}-\dfrac{-1}{5}=\dfrac{3}{5}+\dfrac{1}{5}=\dfrac{4}{5}\)

ai giúp mik vs

c: Ta có: \(\left|x+\dfrac{5}{6}\right|:\dfrac{4}{5}=\dfrac{3}{8}\)

\(\Leftrightarrow\left|x+\dfrac{5}{6}\right|=\dfrac{3}{8}\cdot\dfrac{4}{5}=\dfrac{3}{10}\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{5}{6}=\dfrac{3}{10}\\x+\dfrac{5}{6}=-\dfrac{3}{10}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{-8}{15}\\x=-\dfrac{17}{15}\end{matrix}\right.\)

\(a,=\dfrac{9}{12}-\dfrac{7}{12}-\dfrac{8}{12}=-\dfrac{1}{2}\\ b,=\dfrac{95}{6}+\dfrac{17}{18}-\dfrac{5}{12}=\dfrac{589}{36}\)