Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a. \(\dfrac{5}{7}+\dfrac{4}{3}:x=\dfrac{1}{7}\)
<=> \(\dfrac{5}{7}+\dfrac{4}{3}.\dfrac{1}{x}=\dfrac{1}{7}\)
<=> \(\dfrac{5}{7}+\dfrac{4}{3x}=\dfrac{1}{7}\) ĐKXĐ: x \(\ne\) 0
<=> \(\dfrac{15x}{21x}+\dfrac{28}{21x}=\dfrac{3x}{21x}\)
<=> 15x + 28 = 3x
<=> 15x - 3x = -28
<=> 12x = -28
<=> x = \(\dfrac{-28}{12}=-\dfrac{7}{3}\)
b. \(\dfrac{5}{3}x.\dfrac{-1}{4}=\dfrac{2}{6}\)
<=> \(\dfrac{-5x}{12}=\dfrac{2}{6}\)
<=> -5x . 6 = 12 . 2
<=> -30x = 24
<=> x = \(-\dfrac{4}{5}\)
xin sua cho tôi học giỏi toán nhe
5-2/3x:1/7=23/6
2/3x:1/7=5-23/6
2/3x*7=7/6
2/3x=7/6:7
2/3x=1/6
den day la dung roi
2/3x=2/12=1/6 (vut phan gach ngang di)
Con 3x=12=>x=4
D/S:x=4
5-2/3x:1/7=23/6
2/3x:1/7=5-23/6
2/3x*7=7/6
2/3x=7/6:7
2/3x=1/6
x=1/6:2/3
x=1/4
`@` `\text {Ans}`
`\downarrow`
\(\dfrac{2}{3}\times x-\dfrac{x}{2}-\dfrac{1}{2}=\dfrac{1}{4}?\)
`=>`\(\dfrac{2}{3}x-\dfrac{x}{2}-\dfrac{1}{2}=\dfrac{1}{4}\)
`=>`\(\dfrac{4x}{6}-\dfrac{3x}{6}-\dfrac{1}{2}=\dfrac{1}{4}\)
`=>`\(\dfrac{x}{6}-\dfrac{1}{2}=\dfrac{1}{4}\)
`=>`\(\dfrac{x}{6}=\dfrac{1}{4}+\dfrac{1}{2}\)
`=>`\(\dfrac{x}{6}=\dfrac{3}{4}\)
`=> 4x=3*6`
`=> 4x=18`
`=> x=`\(\dfrac{18}{4}=\dfrac{9}{2}=4,5\)
Vậy, `x=4,5.`
\(\href{https://hoc24.vn/vip/14874167551162}{\text{_KaizulvG_}}\)
A.\(\left(\frac{4}{7}.x-1\right).3=\frac{1}{21}\)
\(\frac{4}{7}.x-1=\frac{1}{21}:3\)
\(\frac{4}{7}.x-1=\frac{1}{21}.3\)
\(\frac{4}{7}.x-1=\frac{1}{7}\)
\(\frac{4}{7}.x=1+\frac{1}{7}\)
\(\frac{4}{7}.x=\frac{8}{7}\)
\(x=\frac{8}{7}:\frac{4}{7}\)
\(x=\frac{8}{7}.\frac{7}{4}\)
\(x=2\)
Vậy x=2
C.\(\frac{2}{3}.x-\frac{1}{3}.x=\frac{5}{9}\)
\(\left(\frac{2}{3}-\frac{1}{3}\right).x=\frac{5}{9}\)
\(\frac{1}{3}.x=\frac{5}{9}\)
\(x=\frac{5}{9}:\frac{1}{3}\)
\(x=\frac{5}{9}.3\)
\(x=\frac{5}{3}\)
Vậy \(x=\frac{5}{3}\)
D. \(\left(x-2\frac{1}{4}\right).\left(\frac{-2}{3}\right).50\%=2\frac{5}{6}\)
\(x.\frac{-2}{3}-\frac{9}{4}.\frac{-2}{3}=\frac{17}{6}:\frac{1}{2}\)
\(x.\frac{-2}{3}-\frac{-3}{2}=\frac{17}{6}.2\)
\(x.\frac{-2}{3}+\frac{3}{2}=\frac{17}{3}\)
\(x.\frac{-2}{3}=\frac{17}{3}-\frac{3}{2}\)
\(x.\frac{-2}{3}=\frac{34}{6}-\frac{9}{6}\)
\(x.\frac{-2}{3}=\frac{25}{6}\)
\(x=\frac{25}{6}:\frac{-2}{3}\)
\(x=\frac{25}{6}.\frac{3}{-2}\)
\(x=\frac{25}{-4}\)
Vậy \(x=\frac{25}{-4}\)
a: \(\Leftrightarrow\left(x-\dfrac{2}{5}\right):\dfrac{3}{2}=-\dfrac{5}{4}+\dfrac{5}{2}=\dfrac{5}{4}\)
\(\Leftrightarrow x-\dfrac{2}{5}=\dfrac{5}{4}\cdot\dfrac{3}{2}=\dfrac{15}{8}\)
hay x=91/40
b: \(\Leftrightarrow\left(2.5x-3.6\right)=-1\cdot\dfrac{12}{7}=\dfrac{-12}{7}\)
=>2,5x=66/35
hay x=132/175
c: \(\Leftrightarrow\left(\dfrac{15}{4}-2x\right)=\dfrac{19}{9}:\dfrac{4}{3}=\dfrac{19}{9}\cdot\dfrac{3}{4}=\dfrac{19}{12}\)
=>2x=15/4-19/12=45/12-19/12=26/12
=>x=13/12
\(x-2.5=\frac{1}{3}+\frac{2x}{3}\)
\(\Leftrightarrow\frac{3\left(x-2,5\right)}{3}=\frac{2x+1}{3}\)
\(\Leftrightarrow3x-7,5=2x+1\)
\(\Leftrightarrow x=8,5\)
\(x-2,5=\frac{1}{3}+\frac{2}{3}x\)
\(x-\frac{2}{3}x=\frac{1}{3}+2,5\)
\(\frac{1}{3}x=\frac{1}{3}+\frac{5}{2}\)
\(\frac{1}{3}x=\frac{17}{6}\)
\(x=\frac{17}{2}\)