\(\dfrac{x}{3}=\dfrac{7}{9}\)
\(\Rightarrow9x=3.7=21\)
\(\Rightarrow x=\dfrac{21}{9}=\dfrac{7}{3}\)
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Bài 2:Tìm x biết:
a)dfrac{1}{7}+xdfrac{-2}{3}
b)dfrac{-2}{3}:xdfrac{-5}{6}
c)left{dfrac{3}{5}-2xright}.dfrac{5}{8}1
d)dfrac{3}{4}+dfrac{2}{5}xdfrac{29}{60}
e)dfrac{3}{4}+dfrac{1}{4}:xdfrac{2}{5}
f)dfrac{11}{12}-left(dfrac{2}{5}+xright)dfrac{2}{3}
g)left|X+dfrac{1}{3}right|-4dfrac{-1}{2}
h)left(dfrac{1}{32}right)^x.8^{2x}512
i)5,3x+left(-3,3right)x+1,7-4,9
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Bài 2:Tìm x biết:
a)\(\dfrac{1}{7}+x=\dfrac{-2}{3}\)
b)\(\dfrac{-2}{3}:x=\dfrac{-5}{6}\)
c)\(\left\{\dfrac{3}{5}-2x\right\}.\dfrac{5}{8}=1\)
d)\(\dfrac{3}{4}+\dfrac{2}{5}x=\dfrac{29}{60}\)
e)\(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)
f)\(\dfrac{11}{12}-\left(\dfrac{2}{5}+x\right)=\dfrac{2}{3}\)
g)\(\left|X+\dfrac{1}{3}\right|-4=\dfrac{-1}{2}\)
h)\(\left(\dfrac{1}{32}\right)^x.8^{2x}=512\)
i)\(5,3x+\left(-3,3\right)x+1,7=-4,9\)
Dạng 2: Tìm x
Bài 1: Tìm x biết:
a) dfrac{x-1}{9} dfrac{8}{3} b) (dfrac{3x}{7}+1) : (-4) dfrac{-1}{8} c) x + dfrac{7}{12} dfrac{17}{18}- dfrac{1}{9}
d) 0,5x - dfrac{2}{3}x dfrac{7}{12} e) dfrac{29}{30}- (dfrac{13}{23}+x) dfrac{7}{46} f) (x + dfrac{1}{4}-dfrac{1}{3}) : (2 + dfrac{1}{6}-dfrac{1}{4}) dfrac{7}{46}
g) dfrac{13}{15}- (dfrac{13}{21}+x) . dfrac{7}{12} dfrac{7}{10} h) 2. middfrac{1}{2}x-...
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Dạng 2: Tìm x
Bài 1: Tìm x biết:
a) \(\dfrac{x-1}{9}\) = \(\dfrac{8}{3}\) b) (\(\dfrac{3x}{7}+1\)) : (-4) = \(\dfrac{-1}{8}\) c) x + \(\dfrac{7}{12}\) = \(\dfrac{17}{18}-\) \(\dfrac{1}{9}\)
d) 0,5x - \(\dfrac{2}{3}x\) = \(\dfrac{7}{12}\) e) \(\dfrac{29}{30}-\) (\(\dfrac{13}{23}+x\)) = \(\dfrac{7}{46}\) f) (x + \(\dfrac{1}{4}-\dfrac{1}{3}\)) : (2 + \(\dfrac{1}{6}-\dfrac{1}{4}\)) =\(\dfrac{7}{46}\)
g) \(\dfrac{13}{15}-\) (\(\dfrac{13}{21}+x\)) . \(\dfrac{7}{12}\) = \(\dfrac{7}{10}\) h) 2. \(\mid\)\(\dfrac{1}{2}x-\dfrac{1}{3}\)\(\mid\) \(-\) \(\dfrac{3}{2}\) = \(\dfrac{1}{4}\) i) 3.(\(3x-\dfrac{1}{2}\))3 + \(\dfrac{1}{9}=0\)
Bài 2: Tìm các số nguyên x, y sao cho:
a) \(\dfrac{x}{3}\) = \(\dfrac{4}{y}\) ; b) \(\dfrac{x}{y}\) = \(\dfrac{2}{7}\)
Bài 3: Tìm \(x \in\)Z thỏa mãn: a) 10 + \(\mid\)\(x\)\(\) - 2\(\mid\) = 19 b) \(\mid\)\(x\) -3\(\mid\) < 5 c) 3. \(\mid\)\(x\) + 2\(\mid\) + 1 = 28
dfrac{5}{left|xright|} - dfrac{4}{3} dfrac{38}{24} -dfrac{1}{7} . ( 9dfrac{1}{2} - 8,75 ) : dfrac{2}{7} + 0,625 : ( -1dfrac{2}{3} )
dfrac{7}{9} - dfrac{left|xright|}{3} dfrac{1}{9} [ dfrac{4}{9} + ( dfrac{3}{8} x - dfrac{1}{2} ) ] . dfrac{6}{11} dfrac{18}{55}
dfrac{2}{9} . ( 3x - dfrac{1}{2} ) - dfrac{5}{6} -1dfrac{1}{3}
Đọc tiếp
\(\dfrac{5}{\left|x\right|}\) - \(\dfrac{4}{3}\) = \(\dfrac{38}{24}\) -\(\dfrac{1}{7}\) . ( 9\(\dfrac{1}{2}\) - 8,75 ) : \(\dfrac{2}{7}\) + 0,625 : ( -1\(\dfrac{2}{3}\) )
\(\dfrac{7}{9}\) - \(\dfrac{\left|x\right|}{3}\) = \(\dfrac{1}{9}\) [ \(\dfrac{4}{9}\) + ( \(\dfrac{3}{8}\) x - \(\dfrac{1}{2}\) ) ] . \(\dfrac{6}{11}\) = \(\dfrac{18}{55}\)
\(\dfrac{2}{9}\) . ( 3x - \(\dfrac{1}{2}\) ) - \(\dfrac{5}{6}\) = -1\(\dfrac{1}{3}\)
28 tháng 5 2021 lúc 16:23
Tìm x biết: (x-\(\dfrac{2}{3}\))\(^2\)=\(\dfrac{5}{6}\)
\(\dfrac{7}{9}\) - \(\dfrac{\left|X\right|}{3}\) = \(\dfrac{1}{9}\)
a)(dfrac{2}{9}(6x-dfrac{3}{4})-3(dfrac{1}{4}x-dfrac{1}{5})dfrac{-8}{15}
b)dfrac{3}{4}(x-dfrac{8}{9})-5(x-dfrac{11}{15})+dfrac{1}{2}x5dfrac{1}{12}
c)dfrac{2}{3}(-3x-dfrac{6}{5})-dfrac{5}{7}(dfrac{49}{15}-14x)-2dfrac{1}{3}
d)(12dfrac{7}{8}-10dfrac{13}{8}):x-1dfrac{7}{33}:dfrac{8}{11}1dfrac{2}{3}
Đọc tiếp
a)(\(\dfrac{2}{9}\)(6x-\(\dfrac{3}{4}\))-3(\(\dfrac{1}{4}\)x-\(\dfrac{1}{5}\))=\(\dfrac{-8}{15}\)
b)\(\dfrac{3}{4}\)(x-\(\dfrac{8}{9}\))-5(x-\(\dfrac{11}{15}\))+\(\dfrac{1}{2}\)x=5\(\dfrac{1}{12}\)
c)\(\dfrac{2}{3}\)(-3x-\(\dfrac{6}{5}\))-\(\dfrac{5}{7}\)(\(\dfrac{49}{15}\)-14x)=-2\(\dfrac{1}{3}\)
d)(12\(\dfrac{7}{8}\)-10\(\dfrac{13}{8}\)):x-1\(\dfrac{7}{33}\):\(\dfrac{8}{11}\)=1\(\dfrac{2}{3}\)
Bài 1:
\(a,\dfrac{62}{7}.x=\dfrac{29}{9}:\dfrac{3}{56}\)
\(b,\dfrac{1}{5}:x=\dfrac{1}{5}-\dfrac{1}{7}\)
\(c,x-\left(\dfrac{50x}{100}+\dfrac{25x}{200}\right)=11\dfrac{1}{4}\)(11 và 1/4 là hỗn số chứ ko phải là 11.1/4 các bn nhé)
\(d,x-\dfrac{25x}{100}=60-x+\dfrac{25x}{100}\)
Tìm x, biết
a)\([x]=0,37\)
b)\(\dfrac{x}{169}=\dfrac{104}{x}\)
c)\(\dfrac{x+9}{15}=\dfrac{3}{5}\)
8 tháng 9 2017 lúc 12:19
tìm x
\(\dfrac{5}{3}x-2\dfrac{1}{3}=-\dfrac{4}{3}.1\dfrac{1}{8}-\dfrac{2}{3}\)
\(2\dfrac{1}{6}:x-\dfrac{-5}{8}=\dfrac{-7}{15}:4\dfrac{1}{5}-\dfrac{-6}{7}\)
\(\left(\dfrac{5}{6}x-0,3\right):2\dfrac{1}{3}=25\%\)
\(\dfrac{4}{7}-\dfrac{2}{3}x=1,5+\dfrac{4}{5}x\)
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