(2x-1):10/7=28/15:4/3
giúp mik với
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
`@` `\text {Ans}`
`\downarrow`
`3,8 * 2x = 1/4*8/3`
`=> 3,8*2x = 2/3`
`=> 2x = 2/3 \div 3,8`
`=> 2x = 10/57`
`=> x = 10/57 \div 2`
`=> x = 5/57`
Vậy, `x = 5/57.`
<=>\(\left|\dfrac{1}{2}-2x\right|=\dfrac{5}{3}< =>\left[{}\begin{matrix}\dfrac{1}{2}-2x=\dfrac{5}{3}\\\dfrac{1}{2}-2x=\dfrac{-5}{3}\end{matrix}\right.< =>\left[{}\begin{matrix}2x=\dfrac{-7}{6}\\2x=\dfrac{13}{6}\end{matrix}\right.< =>\left[{}\begin{matrix}x=\dfrac{-7}{12}\\x=\dfrac{13}{12}\end{matrix}\right.\)
\(\left|\dfrac{1}{2}+2x\right|+\dfrac{2}{3}=\dfrac{7}{3}\)
\(\left|\dfrac{1}{2}+2x\right|=\dfrac{7}{3}-\dfrac{2}{3}=\dfrac{5}{3}\)
⇔\(\left[{}\begin{matrix}\dfrac{1}{2}+2x=\dfrac{5}{3}\\\dfrac{1}{2}+2x=-\dfrac{5}{3}\end{matrix}\right.\)
⇔ \(\left[{}\begin{matrix}x=\dfrac{7}{12}\\x=-\dfrac{13}{12}\end{matrix}\right.\)
Vậy ...
bạn đã kiểm tra kĩ chưa vậy?mình đọc đề câu B mà loạn não luôn á;-;
\(\left(2x-1\right)\div\frac{10}{7}=\frac{28}{15}\div\frac{4}{3}\)
\(\Leftrightarrow\frac{2x-1}{\frac{10}{7}}=\frac{\frac{28}{15}}{\frac{4}{3}}\)
\(\Leftrightarrow\frac{4}{3}\left(2x-1\right)=\frac{10}{7}\times\frac{28}{15}\)
\(\Leftrightarrow\frac{4}{3}\left(2x-1\right)=\frac{8}{3}\)
\(\Leftrightarrow2x-1=2\)
\(\Leftrightarrow2x=3\)
\(\Leftrightarrow x=\frac{3}{2}\)
hok tốt nhé!
a, 3x - 2x < 6 <=> x < 6
b, đk : x khác -1 ; 3
=> x^2 - 3x = x^2 - x - 2
<=> -2x = -2 <=> x = 1 (tm)
mình chỉ tính vế bên thôi nhé bn tích x
\(\frac{1}{4.7}+\frac{1}{7.10}+...+\frac{1}{25.28}\)
\(\frac{1}{3}\left(\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-.....+\frac{1}{25}-\frac{1}{28}\right)\)
=\(\frac{1}{3}\left(\frac{1}{4}-\frac{1}{28}\right)\)
=\(???\)
\(a,\left|2x+\dfrac{1}{2}\right|=0\\ \Leftrightarrow2x+\dfrac{1}{2}=0\\ \Leftrightarrow2x=-\dfrac{1}{2}\\ \Leftrightarrow x=-\dfrac{1}{4}\\ b,\left|3x+\dfrac{3}{4}\right|=3\\ \Leftrightarrow\left[{}\begin{matrix}3x+\dfrac{3}{4}=3\\3x+\dfrac{3}{4}=-3\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}3x=\dfrac{9}{4}\\3x=-\dfrac{15}{4}\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{4}\\x=-\dfrac{5}{4}\end{matrix}\right.\)
\(\left(2x-1\right):\dfrac{10}{7}=\dfrac{28}{15}:\dfrac{4}{3}\)
\(\Rightarrow\left(2x-1\right).\dfrac{7}{10}=\dfrac{28}{15}.\dfrac{3}{4}\)
\(\Rightarrow\left(2x-1\right).\dfrac{7}{10}=\dfrac{7}{5}\)
\(\Rightarrow2x-1=\dfrac{7}{5}:\dfrac{7}{10}\)
\(\Rightarrow2x-1=\dfrac{7}{5}.\dfrac{10}{7}\)
\(\Rightarrow2x-1=2\)
\(\Rightarrow2x=3\)
\(\Rightarrow x=\dfrac{3}{2}\)
Cảm ơn bạn