\(\dfrac{3}{x}-\dfrac{2}{5}=-\dfrac{11}{40}\\ =>\dfrac{3}{x}=-\dfrac{11}{40}+\dfrac{2}{5}\\ =>\dfrac{3}{x}=\dfrac{1}{8}\\ =>x=\dfrac{3.8}{1}=24\)
Tìm x:
a)\(2016x+\left(\dfrac{7}{12}+\dfrac{4}{21}+\dfrac{2}{24}+\dfrac{11}{30}+\dfrac{3}{40}+\dfrac{15}{56}\right)-\left(\dfrac{2}{3}+\dfrac{2}{4}+\dfrac{2}{5}\right)=0\)
b\(\dfrac{2x-1}{x+2015}-\dfrac{4025}{x+2017}=\dfrac{x-2014}{2x-4036}-\dfrac{x-2013}{2x-4030}\) (x thuộc N)
c)\(\left(1+\dfrac{1}{1.3}\right)\left(1+\dfrac{1}{2.4}\right)\left(1+\dfrac{1}{3.5}\right)...\left(1+\dfrac{1}{x\left(x+2\right)}\right)=\dfrac{4016}{2007}\)
AI GIÚP MK VỚI MK TICK CHO 
1. Tìm x , biết
\(\dfrac{11}{12}+\dfrac{11}{12.13}+\dfrac{11}{23.24}+....+\dfrac{11}{59.100}+x=\dfrac{5}{3}\)
Tìm x biết:
a) \(\dfrac{x+5}{3}\)=\(\dfrac{x-6}{7}\)
b) x - \(\dfrac{20}{11.13}\)-\(\dfrac{20}{13.15}\)-\(\dfrac{20}{15.17}\)-...-\(\dfrac{20}{53.55}\)=\(\dfrac{3}{11}\)
\(\dfrac{1}{3}\)+\(\dfrac{1}{6}\)+\(\dfrac{1}{10}\)+...+\(\dfrac{2}{n\left(n+1\right)}\)=\(\dfrac{2015}{2016}\)
tìm x
\([\dfrac{6:\dfrac{3}{5}-1\dfrac{1}{16}.\dfrac{16}{7}}{4\dfrac{1}{5}-\dfrac{10}{11}+5\dfrac{2}{11}}-\dfrac{\left(\dfrac{3}{20}+\dfrac{1}{2}-\dfrac{1}{5}\right).\dfrac{12}{49}}{3\dfrac{1}{3}+\dfrac{2}{9}}].x=2\dfrac{23}{96}\)
Tìm x biết:
\(\dfrac{3}{4}.x+\dfrac{1}{5}=\dfrac{1}{6}\)
b)(\(4\dfrac{1}{2}-\dfrac{2}{5}x\)):\(\dfrac{7}{4}=\dfrac{11}{14}\)
BT3: Tìm x, biết
13) \(\left(-1\dfrac{1}{5}+x\right):\left(-3\dfrac{3}{5}\right)=\dfrac{-7}{4}+\dfrac{1}{4}:\dfrac{1}{8}\)
14) \(\dfrac{11}{13}-\left(\dfrac{5}{42}-x\right)=-\left(\dfrac{15}{28}-\dfrac{11}{13}\right)\)
Tìm x biết :
1/\(\dfrac{4}{3}\) + x = \(\dfrac{2}{15}\) 2/\(\dfrac{1}{3}+\dfrac{1}{2}:\) x = -0,25 3/(\(\dfrac{2x}{5}+2\) ):(-4) = -1\(\dfrac{1}{2}\) 4/ x.( x + 1) = 0 5/3\(\dfrac{1}{2}-\dfrac{1}{2}x\) = \(\dfrac{2}{3}\)
6/1\(\dfrac{1}{2}+x=\dfrac{3}{2}-7\) 7/\(2x-16=40+x\) 8/\(x:\dfrac{5}{3}+\dfrac{1}{3}=\dfrac{-2}{5}\) 9/\(\dfrac{x}{4}=\dfrac{9}{x}\)
1)tìm x
a)\(\dfrac{2}{3}x+\dfrac{5}{7}=\dfrac{3}{10}\) b)\(\dfrac{11}{12}-\left(\dfrac{2}{5}+x\right)=\dfrac{2}{3}\) c)\(2\cdot\left(2x-\dfrac{1}{7}\right)=0\) d)\(\left(3-2x\right)\left(7x-\dfrac{1}{8}\right)=0\)
2)xác định giá trị của để:
a)\(\dfrac{x+3}{x-5}\)có giá trị âm b)\(\left(x+\dfrac{2}{3}\right)\cdot\left(x-2\right)>0\)
giúp mình !
Bài 1: Tính ( hợp lý nếu có thể)
A=\(\dfrac{-3}{8}\)+\(\dfrac{12}{25}\)+\(\dfrac{5}{-8}\)+\(\dfrac{2}{-5}\)+\(\dfrac{13}{25}\)
B=\(\dfrac{-3}{15}\)+(\(\dfrac{2}{3}\)+\(\dfrac{3}{15}\))
C=\(\dfrac{-5}{21}\)+(\(\dfrac{-16}{21}\)+1)
D=(\(\dfrac{-1}{6}\)+\(\dfrac{5}{-12}\))+\(\dfrac{7}{12}\)
E=\(\dfrac{1}{3}\)x\(\dfrac{4}{5}\)+\(\dfrac{1}{3}\)x\(\dfrac{6}{5}\)+\(\dfrac{2}{3}\)
F=\(\dfrac{-5}{6}\)x\(\dfrac{4}{19}\)+\(\dfrac{-7}{12}\)x\(\dfrac{4}{12}\)-\(\dfrac{40}{47}\)
Bài 2: Tìm x,biết:
a) x + \(\dfrac{2}{3}\) = \(\dfrac{4}{5}\)
b) x - \(\dfrac{2}{3}\) = \(\dfrac{7}{21}\)
c) -x - \(\dfrac{3}{4}\) =\(\dfrac{-8}{11}\)
d) \(\dfrac{11}{12}\) - (\(\dfrac{2}{5}\) + x) = \(\dfrac{2}{3}\)
