a: -12/x=3/5
=>x=-12x5:3=-20
b: (x-1)+(x-2)+(x-3)+...+(x-20)=10
=>20x-210=10
=>20x=220
hay x=11
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MN
4 tháng 3 2022 lúc 8:35
Tìm x, biết:a) dfrac{3}{4}x - dfrac{7}{12} dfrac{5}{6} - dfrac{2}{3}b) -dfrac{5}{x} dfrac{20}{28}c) 2dfrac{1}{3} : x 7d) dfrac{-105}{12} x dfrac{20}{7}
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Tìm x, biết:
a) \(\dfrac{3}{4}x\) - \(\dfrac{7}{12}\) = \(\dfrac{5}{6}\) - \(\dfrac{2}{3}\)
b) -\(\dfrac{5}{x}\) = \(\dfrac{20}{28}\)
c) \(2\dfrac{1}{3}\) : x = 7
d) \(\dfrac{-105}{12}\) < x < \(\dfrac{20}{7}\)
Tìm x biết: a) \(\left(x-\dfrac{1}{2}\right)\left(-3-\dfrac{x}{2}\right)=0\) b) \(x-\dfrac{1}{8}=\dfrac{5}{8}\)
c) \(-\dfrac{1}{2}-\left(\dfrac{3}{2}+x\right)=-2\) d) \(x+\dfrac{1}{3}=\dfrac{-12}{5}.\dfrac{10}{6}\)
KJ
28 tháng 12 2021 lúc 15:20
Tìm số nguyên x, y biết:
\(a,\dfrac{x}{5}=\dfrac{-18}{10}\) b, \(\dfrac{6}{x-1}=\)\(\dfrac{-3}{7}\) c, \(\dfrac{y-3}{12}\)=\(\dfrac{3}{y-3}\) d, \(\dfrac{x}{25}\)=\(\dfrac{-5}{x^2}\)
tìm x :a, x . dfrac{-5}{8} dfrac{15}{32} b, dfrac{3}{10} : x dfrac{-9}{20}c, dfrac{-1}{4} x + dfrac{4}{5} dfrac{3}{4} d, dfrac{-7}{8} + dfrac{2}{3} :x dfrac{3}{5} . dfrac{-5}{12}
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tìm x :
a, x . \(\dfrac{-5}{8}\) = \(\dfrac{15}{32}\) b, \(\dfrac{3}{10}\) : x =\(\dfrac{-9}{20}\)
c, \(\dfrac{-1}{4}\) x + \(\dfrac{4}{5}\) =\(\dfrac{3}{4}\) d, \(\dfrac{-7}{8}\) + \(\dfrac{2}{3}\) :x = \(\dfrac{3}{5}\) . \(\dfrac{-5}{12}\)
tìm x biết
a , \(\dfrac{-3}{10}\)-(\(\dfrac{-1}{5}\) +x)=\(\dfrac{-3}{2}\)
b, -(-x+ \(\dfrac{3}{4}\))- \(\dfrac{12}{8}\).- \(\dfrac{32}{15}\)=- \(\dfrac{-1}{2}\)
c, \(\dfrac{x-3}{x+5}\)=\(\dfrac{4}{3}\)
a) x + dfrac{2}{5} dfrac{1}{2}b) x - dfrac{2}{5} dfrac{2}{7}c) dfrac{3}{5} - x dfrac{1}{10}d) x . dfrac{3}{4} dfrac{9}{20}e) x : dfrac{1}{7} 14f) ( dfrac{1}{4} + x ) . dfrac{1}{2} dfrac{2}{5}g) x . dfrac{2}{3} - dfrac{2}{3} dfrac{9}{12}h) dfrac{3}{4} + dfrac{1}{4} : x dfrac{2}{5}k) 3dfrac{4}{5} - x dfrac{18}{5}l) x . 2dfrac{1}{3} dfrac{3}{4}m) x . dfrac{6}{11} + x . dfrac{5}{11} 2025n) x . dfrac{14}{9} - x . dfrac{7}{9} + x . dfrac{5}{9} 2Các bạn làm theo cách bình thường ở lớp...
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a) x + \(\dfrac{2}{5}\) = \(\dfrac{1}{2}\)
b) x - \(\dfrac{2}{5}\) = \(\dfrac{2}{7}\)
c) \(\dfrac{3}{5}\) - x = \(\dfrac{1}{10}\)
d) x . \(\dfrac{3}{4}\) = \(\dfrac{9}{20}\)
e) x : \(\dfrac{1}{7}\) = 14
f) ( \(\dfrac{1}{4}\) + x ) . \(\dfrac{1}{2}\) = \(\dfrac{2}{5}\)
g) x . \(\dfrac{2}{3}\) - \(\dfrac{2}{3}\) = \(\dfrac{9}{12}\)
h) \(\dfrac{3}{4}\) + \(\dfrac{1}{4}\) : x = \(\dfrac{2}{5}\)
k) \(3\dfrac{4}{5}\) - x = \(\dfrac{18}{5}\)
l) x . \(2\dfrac{1}{3}\) = \(\dfrac{3}{4}\)
m) x . \(\dfrac{6}{11}\) + x . \(\dfrac{5}{11}\) = 2025
n) x . \(\dfrac{14}{9}\) - x . \(\dfrac{7}{9}\) + x . \(\dfrac{5}{9}\) = 2
Các bạn làm theo cách bình thường ở lớp 5 cho mính nhé!
Chú ý: dấu "." là dấu nhân.
KJ
4 tháng 1 2022 lúc 14:32
Tìm x, y, z, t ∈ Z biết:a, dfrac{5}{x}dfrac{-10}{12} b, dfrac{4}{-6}dfrac{x+3}{9} c, dfrac{x-1}{25}dfrac{4}{x-1} d, dfrac{x+1}{y}dfrac{-3}{5}e, dfrac{-12}{6}dfrac{x}{5}dfrac{-y}{3}dfrac{Z}{-17}dfrac{-t}{-9}h, dfrac{-24}{-6}dfrac{x}{3}dfrac{4}{y^2}dfrac{Z^3}{-2}
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Tìm x, y, z, t ∈ Z biết:
a, \(\dfrac{5}{x}=\dfrac{-10}{12}\) b, \(\dfrac{4}{-6}=\dfrac{x+3}{9}\) c, \(\dfrac{x-1}{25}=\dfrac{4}{x-1}\) d, \(\dfrac{x+1}{y}=\dfrac{-3}{5}\)
e, \(\dfrac{-12}{6}=\dfrac{x}{5}=\dfrac{-y}{3}=\dfrac{Z}{-17}=\dfrac{-t}{-9}\)
h, \(\dfrac{-24}{-6}=\dfrac{x}{3}=\dfrac{4}{y^2}=\dfrac{Z^3}{-2}\)
tìm x , biết:a) x : 4dfrac{1}{3} -2,5 b) dfrac{3}{5}x + dfrac{1}{4} dfrac{1}{10}c) 2dfrac{7}{9} - dfrac{12}{13}x dfrac{7}{9} d)dfrac{-2}{3}-dfrac{1}{3}left(2x-5right)dfrac{3}{2}
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tìm x , biết:
a) \(x\) : \(4\dfrac{1}{3}\) = -2,5 b) \(\dfrac{3}{5}x\) + \(\dfrac{1}{4}\) = \(\dfrac{1}{10}\)
c) \(2\dfrac{7}{9}\) \(-\) \(\dfrac{12}{13}x\) = \(\dfrac{7}{9}\) d)\(\dfrac{-2}{3}-\dfrac{1}{3}\)\(\left(2x-5\right)=\dfrac{3}{2}\)
HV
6 tháng 3 2022 lúc 18:09
Bài 9: Tìm x biết1) dfrac{9}{x}dfrac{-35}{105} 2) dfrac{12}{5}dfrac{32}{x} 3) dfrac{x}{2}dfrac{32}{x} 4) dfrac{x-2}{4}dfrac{x-1}{5}Bài 10: Cho biểu thức Adfrac{3}{n+2}a) Số nguyên n phài thỏa mãn điều kiện gì để A là phân số? b) Tìm phân số A khi n 0? n 2? n -7?
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Bài 9: Tìm \(x\) biết
1) \(\dfrac{9}{x}=\dfrac{-35}{105}\) 2) \(\dfrac{12}{5}=\dfrac{32}{x}\) 3) \(\dfrac{x}{2}=\dfrac{32}{x}\) 4) \(\dfrac{x-2}{4}=\dfrac{x-1}{5}\)
Bài 10: Cho biểu thức \(A=\dfrac{3}{n+2}\)
a) Số nguyên n phài thỏa mãn điều kiện gì để A là phân số? b) Tìm phân số A khi n = 0? n = 2? n = -7?