-7*(2-3x)=(1+2x)*5
-14+21x=5+10x
21x-10x=5+14
11x=19
=>x=19/11
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Tìm x :
a) dfrac{2x-3}{3}+dfrac{-3}{2}dfrac{5-3x}{6}-dfrac{1}{3}
b) dfrac{2}{3x}-dfrac{3}{12}dfrac{4}{5}-left(dfrac{7}{x}-2right)
c) dfrac{x+2014}{2}+dfrac{2x+4028}{7}dfrac{x+2009}{5}+dfrac{x+2020}{6}
d)dfrac{3}{left(x+2right)left(x+5right)}+dfrac{5}{left(x+5right)left(x+10right)}+dfrac{7}{left(x+10right)left(x+18right)}dfrac{x}{left(x+2right)left(x+17right)}
Help me , bn nào giải đc bài nò thì giải nha !!! ))
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Tìm x :
a) \(\dfrac{2x-3}{3}+\dfrac{-3}{2}=\dfrac{5-3x}{6}-\dfrac{1}{3}\)
b) \(\dfrac{2}{3x}-\dfrac{3}{12}=\dfrac{4}{5}-\left(\dfrac{7}{x}-2\right)\)
c) \(\dfrac{x+2014}{2}+\dfrac{2x+4028}{7}=\dfrac{x+2009}{5}+\dfrac{x+2020}{6}\)
d)\(\dfrac{3}{\left(x+2\right)\left(x+5\right)}+\dfrac{5}{\left(x+5\right)\left(x+10\right)}+\dfrac{7}{\left(x+10\right)\left(x+18\right)}=\dfrac{x}{\left(x+2\right)\left(x+17\right)}\)
Help me , bn nào giải đc bài nò thì giải nha !!! =))
tìm x , biết :
a, dfrac{37-x}{2x+5}dfrac{4}{9}
b, dfrac{x-2}{x-1}dfrac{x+4}{x+7}
c, dfrac{x+3}{25}dfrac{9}{x+3}
d, dfrac{x}{dfrac{-2}{3}}dfrac{5}{-x}
e, dfrac{2x-5}{dfrac{3}{2}}dfrac{dfrac{-27}{8}}{5-2x}
f, dfrac{dfrac{5}{9}}{left(3x-1right)^2}dfrac{1-2x}{dfrac{25}{3}}
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tìm x , biết :
a, \(\dfrac{37-x}{2x+5}=\dfrac{4}{9}\)
b, \(\dfrac{x-2}{x-1}=\dfrac{x+4}{x+7}\)
c, \(\dfrac{x+3}{25}=\dfrac{9}{x+3}\)
d, \(\dfrac{x}{\dfrac{-2}{3}}=\dfrac{5}{-x}\)
e, \(\dfrac{2x-5}{\dfrac{3}{2}}=\dfrac{\dfrac{-27}{8}}{5-2x}\)
f, \(\dfrac{\dfrac{5}{9}}{\left(3x-1\right)^2}=\dfrac{1-2x}{\dfrac{25}{3}}\)
Tìm x, biết: \(7-\dfrac{1}{2}\left(2x-5\right)-\dfrac{2}{3}\left(3x+1\right)=5\)
1 tìm x
\(\dfrac{3}{4}-\left(2x-\dfrac{2}{3}\right)=\dfrac{-5}{6}\)
\(1,5-\left(x+\dfrac{7}{2}\right)=2^7:2^5\)
\(-12\left(\dfrac{1}{2}-3x\right)^3-\sqrt{16}=\left|-46\right|\)
\(\dfrac{3x+2}{5x+7}=\dfrac{3x-1}{5x-3}\)
b,\(\dfrac{\left|2x-1\right|}{\dfrac{1}{2}}=\dfrac{18}{5}\)
Tìm x:
a)\(5\dfrac{4}{7}:\left\{x:1,3+8,4.\dfrac{6}{7}.\left[6-\dfrac{\left(2,3+5:6,25\right).7}{8.0,0125+6,9}\right]\right\}=1\dfrac{1}{14}\)
b)\(\left|3x-2\right|+\left|2x-1\right|=4\)
a,\(\left(3x-2\right):1\dfrac{2}{5}=2\dfrac{3}{7}:2\dfrac{3}{5}\)
b,\(\dfrac{31-2x}{x+23}=\dfrac{9}{4}\)
c,\(\dfrac{x+3}{8}=\dfrac{2}{x-3}\)
d,\(\dfrac{-1,64}{8,51}=\dfrac{\left|x\right|}{-3,11}\)
Tìm x, biết:
a) \(\dfrac{3x+2}{5x+7}=\dfrac{3x-1}{5x+1}\)
b) \(\dfrac{x+1}{2x+1}=\dfrac{0,5x+2}{x+3}\)
cho \(S=\dfrac{1}{5^2}+\dfrac{1}{5^4}+\dfrac{1}{5^6}+...+\dfrac{1}{5^{2018}}\)
a, CMR : \(S< \dfrac{1}{24}\)
b, Có hay ko số nguyên x thỏa mãn : \(3x^7-2x^4+6x^2-18x=501\)