\(\dfrac{5}{7}x-x=1\dfrac{1}{7}\\ < =>\dfrac{5}{7}x-x=\dfrac{8}{7}\\ < =>\left(\dfrac{5}{7}-\dfrac{7}{7}\right)x=\dfrac{8}{7}\\ < =>-\dfrac{2}{7}x=\dfrac{8}{7}\\ =>x=\dfrac{\dfrac{8}{7}}{-\dfrac{2}{7}}=-4\)
\(\dfrac{5}{7}x-x=1\dfrac{1}{7}\\ < =>\dfrac{5}{7}x-x=\dfrac{8}{7}\\ < =>\left(\dfrac{5}{7}-\dfrac{7}{7}\right)x=\dfrac{8}{7}\\ < =>-\dfrac{2}{7}x=\dfrac{8}{7}\\ =>x=\dfrac{\dfrac{8}{7}}{-\dfrac{2}{7}}=-4\)
\(\dfrac{x+3}{15}=\dfrac{1}{3}\)
Giup mik voi mik can gap lam!!!!!!!!
a)x=\(\dfrac{1}{4}+\dfrac{2}{13}\)
b)\(\dfrac{x}{3}=\dfrac{2}{3}+\dfrac{-1}{7}\)
c)\(\dfrac{-8}{3}+\dfrac{-1}{3}\le x\le\dfrac{-2}{7}+\dfrac{-5}{7}\)
d)\(\dfrac{-5}{6}+\dfrac{8}{3}\dfrac{29}{-x}\le x\le\dfrac{-1}{2}+2+\dfrac{5}{2}\)
Bài 2 Tính nhanh
a) \(\dfrac{5}{23}\) x \(\dfrac{17}{26}\) + \(\dfrac{5}{23}\) x \(\dfrac{10}{26}\) - \(\dfrac{5}{23}\)
b) \(\dfrac{1}{7}\) x \(\dfrac{5}{9}\) + \(\dfrac{5}{9}\) x \(\dfrac{2}{7}\) + \(\dfrac{5}{9}\) x \(\dfrac{1}{7}\) + \(\dfrac{5}{9}\) x \(\dfrac{3}{7}\)
tim x , biet :
b, |\(\dfrac{5}{4}\)x-\(\dfrac{7}{2}\)|=|\(\dfrac{5}{8}\)x+\(\dfrac{3}{5}\)|=0
c, |\(\dfrac{7}{5}\)x+\(\dfrac{2}{3}\)|=|\(\dfrac{4}{3}\)x-\(\dfrac{1}{4}\)|
d, |\(\dfrac{7}{8}\)x+\(\dfrac{5}{6}\)|-|\(\dfrac{1}{2}\)x+5|=0
BT3: Tìm x, biết
3) \(\dfrac{3}{4}.x-\dfrac{5}{3}.x=\dfrac{7}{12}\)
4) \(x-\dfrac{1}{7}=\) \(\dfrac{\dfrac{4}{2011}-\dfrac{4}{2013}+\dfrac{4}{99}}{\dfrac{5}{2011}-\dfrac{5}{2013}+\dfrac{5}{99}}+\dfrac{1}{2}\)
Các bạn giúp mk nhé
1. Tim x:
a. \(\dfrac{x}{5}\) = \(\dfrac{5}{6}\) + \(\dfrac{-19}{30}\)
b. \(\dfrac{-5}{6}\) \(-x\) = \(\dfrac{7}{12}\)\(-\) \(\dfrac{1}{3}\)\(\times\) \(x\)
c.2016\(^{^{ }3}\) \(\times\)2016\(^{^{ }x}\) = 2016\(^{^{ }8}\)
d. \((x+\dfrac{3}{4}):\dfrac{5}{2}=3^1_2\)
e. (2,8 \(x\) \(-\) 2\(^5\)) : \(\dfrac{2}{3}=3^2\)
f. \(\dfrac{4}{7}\times x-\dfrac{2}{3}=\dfrac{2}{5}\)
g. \((\dfrac{3x}{7}+1):\left(-4\right)=\dfrac{-1}{28}\)
2. Thuc hien phep tinh:
a. \(\dfrac{1}{2}+\dfrac{1}{2}\times\dfrac{2}{3}-\dfrac{1}{3}:\dfrac{3}{4}+1^4_5\)
b. \(\dfrac{7\times5^2-7^2}{7\times24+21}\)
c. \(\dfrac{2}{3}+\dfrac{1}{3}\times(-\dfrac{4}{9}+\dfrac{5}{6}):\dfrac{7}{12}\)
BT3: Tìm x, biết:
7) \(\dfrac{-5}{17}+\dfrac{3}{17}\le\dfrac{x}{17}\le\dfrac{13}{17}+\dfrac{-11}{17}\)
8) \(\dfrac{2}{3}\left(\dfrac{1}{2}+\dfrac{3}{4}-\dfrac{1}{3}\right)\le\dfrac{x}{18}\le\dfrac{7}{3}\left(\dfrac{1}{2}-\dfrac{1}{6}\right)\)
Tìm x,biết :
\(\dfrac{1}{6} + \dfrac{-5}{7} : x = \dfrac{-7}{8}\)
\(\dfrac{-3}{4}x\dfrac{4}{7}+\dfrac{-3}{5}x\dfrac{3}{7}-\dfrac{2}{5}\)
\(\left(\dfrac{3}{4}x\dfrac{5}{6}-\dfrac{7}{12}\right)x\left(\dfrac{-12}{7}\right)\)
\(1,4x\dfrac{15}{19}x\left(\dfrac{4}{5}x\dfrac{-2}{3}\right)+\dfrac{7}{15}\)
Tính nha