a, (2x - 4)^2 = 36/49

=> 2x - 4 = 6/7 hoặc 2x - 4 = -6/7

=> 2x = 34/7 hoặc x = 22/7

=> x = 34/14 hoặc x = 22/14

b, tương tự a

c, |1 - x| + 0,73 = 3

=> |1 - x| = 2,23

=> 1 - x = 2,23 hoặc 1 - x = -2,23

=> x = -1,23 hoặc x = 3,23

d, tương tự c

a) \(\left(2x-4\right)^2=\frac{36}{49}=\frac{6^2}{7^2}=\left(\frac{6}{7}\right)^2\)

\(\Rightarrow2x-4=\frac{6}{7}\Rightarrow2x=\frac{34}{7}\Rightarrow x=\frac{17}{7}\)

b) \(\left(3x-5\right)^2=\frac{36}{25}=\frac{6^2}{5^2}=\left(\frac{6}{5}\right)^2\)

\(\Rightarrow3x-5=\frac{6}{5}\Rightarrow3x=\frac{31}{5}\Rightarrow x=\frac{31}{15}\)

c)\(\left|1-x\right|+0,73=3\Rightarrow\left|1-x\right|=2,27\)

\(\orbr{\begin{cases}TH1.1-x=2,27\Rightarrow x=-1,27\\TH2.1-x=-2,27\Rightarrow x=3,27\end{cases}}\)

Vậy, x=......

d) \(\left|x+\frac{3}{4}\right|-5=-2\Rightarrow\left|x+\frac{3}{4}\right|=3\)

\(\orbr{\begin{cases}TH1.x+\frac{3}{4}=3\Rightarrow x=\frac{9}{4}\\TH2.x+\frac{3}{4}=-3\Rightarrow x=-3,75\end{cases}}\)

Vậy, x=.......

HOK TỐT

\(\left(x-2y+5\right)+\left(4.5-3x\right)=0\)

\(\Rightarrow x-2y+5+20-3x=0\)

\(\Rightarrow-2x-2y+25=0\)

\(\Rightarrow-2x-2y=-25\)

\(\Rightarrow-2\left(x-y\right)=-25\)

\(\Rightarrow x-y=\frac{25}{2}\)

Chúc em học tốt nhé!

a)

\(7,5.\left(\frac{-2}{5}\right).\left(-2,5\right)\)

\(=7,5.\left[\left(\frac{-2}{5}\right).\left(-2,5\right)\right]\)

\(=7,5.1\)

\(=7,5\)

b) 

\(\left(-50,5\right).8.\left(-0,25\right)\)

\(=\left(-50,5\right).\left[8.\left(-0,25\right)\right]\)

\(=\left(-50,5\right).\left(-2\right)\)

\(=101\)

c)

\(\left(0,125\right).\left(-3,7\right).\left(-2\right)^3\)

\(=\left(0,125\right).\left(-3,7\right).\left(-8\right)\)

\(=\left[\left(-8\right).\left(0,125\right)\right].\left(-3,7\right)\)

\(=\left(-1\right).\left(-3,7\right)\)

\(=3,7\)

Chúc cậu học tốt !!!

\(B=\left(\frac{3}{25}-1,12\right):\frac{3}{7}:\left[\left(3\frac{1}{2}-3\frac{2}{3}\right)\right]\)

\(B=\left(\frac{3}{25}-\frac{28}{25}\right):\frac{3}{7}:\left[\left(\frac{7}{2}-\frac{11}{3}\right)\right]\)

\(B=\frac{-25}{25}:\frac{3}{7}:\left[\left(\frac{21}{6}-\frac{22}{6}\right)\right]\)

\(B=-1:\frac{3}{7}:\frac{-1}{6}\)

\(B=\frac{-1}{1}.\frac{7}{3}:\frac{-1}{6}\)

\(B=\frac{-7}{3}:\frac{-1}{6}\)

\(B=\frac{-7}{3}.\frac{6}{-1}=\frac{-42}{-3}=14\)

Chúc cậu học tốt !!!