B
1
K
Khách
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Các câu hỏi dưới đây có thể giống với câu hỏi trên
6 tháng 6 2016
a) (x + 1/2) . (2/3 − 2x) = 0
\(\Rightarrow\left[\begin{array}{nghiempt}x+\frac{1}{2}=0\\\frac{2}{3}-2x=0\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x=-\frac{1}{2}\\2x=\frac{2}{3}\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x=-\frac{1}{2}\\x=\frac{1}{3}\end{array}\right.\)
b) \(\left(x.6\frac{2}{7}+\frac{3}{7}\right).2\frac{1}{5}-\frac{3}{7}=-2\)
\(\Rightarrow\left(x.\frac{44}{7}+\frac{3}{7}\right).\frac{11}{5}=-2+\frac{3}{7}\)
\(\Rightarrow\left(x.\frac{44}{7}+\frac{3}{7}\right).\frac{11}{5}=-\frac{11}{7}\)
\(\Rightarrow x.\frac{44}{7}+\frac{3}{7}=-\frac{11}{7}:\frac{11}{5}=-\frac{11}{7}.\frac{5}{11}\)
\(\Rightarrow x.\frac{44}{7}+\frac{3}{7}=-\frac{5}{7}\)
\(\Rightarrow x.\frac{44}{7}=-\frac{5}{7}-\frac{3}{7}\)
\(\Rightarrow x.\frac{44}{7}=-\frac{8}{7}\)
\(\Rightarrow x=-\frac{8}{7}:\frac{44}{7}=-\frac{8}{7}.\frac{7}{44}\)
\(\Rightarrow x=-\frac{2}{11}\)
6 tháng 6 2016
c) \(x.3\frac{1}{4}+\left(-\frac{7}{6}\right).x-1\frac{2}{3}=\frac{5}{12}\)
\(\Rightarrow x\left(3\frac{1}{4}-\frac{7}{6}\right)=\frac{5}{12}+\frac{5}{3}\)
\(\Rightarrow x\left(\frac{13}{4}-\frac{7}{6}\right)=\frac{25}{12}\)
\(\Rightarrow x.\frac{25}{12}=\frac{25}{12}\)
\(\Rightarrow x=\frac{25}{12}:\frac{25}{12}\)
\(\Rightarrow x=1\)
d) \(5\frac{8}{17}:x+\left(-\frac{4}{17}\right):x+3\frac{1}{7}:17\frac{1}{3}=\frac{4}{11}\)
\(\Rightarrow\left(5\frac{8}{17}-\frac{4}{17}\right):x+\frac{22}{7}:\frac{52}{3}=\frac{4}{11}\)
\(\Rightarrow5\frac{4}{17}:x+\frac{33}{182}=\frac{4}{11}\)
\(\Rightarrow\frac{89}{17}:x=\frac{4}{11}-\frac{33}{182}\)
\(\Rightarrow\frac{89}{17}:x=\frac{365}{2002}\)
\(\Rightarrow x=\frac{89}{17}:\frac{365}{2002}\)
\(\Rightarrow x\approx28,7\) (số hơi lẻ)
e) \(\frac{17}{2}-\left|2x-\frac{3}{4}\right|=-\frac{7}{4}\)
\(\Rightarrow\left|2x-\frac{3}{4}\right|=\frac{17}{2}+\frac{7}{4}\)
\(\Rightarrow\left|2x-\frac{3}{4}\right|=\frac{41}{4}\)
\(\Rightarrow\left[\begin{array}{nghiempt}2x-\frac{3}{4}=\frac{41}{4}\\2x-\frac{3}{4}=-\frac{41}{4}\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}2x=11\\2x=-\frac{19}{2}\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x=\frac{11}{2}\\x=-\frac{19}{4}\end{array}\right.\)
22 tháng 5 2017
a)\(-\frac{15}{12}x+\frac{3}{7}=\frac{6}{4}x-\frac{1}{2}\)
\(\Leftrightarrow\frac{15}{12}x+\frac{6}{4}x=\frac{1}{2}+\frac{3}{7}\)
\(\Leftrightarrow\frac{11}{4}x=\frac{9}{14}\Leftrightarrow x=\frac{36}{154}\)
b) \(\frac{2}{5}\left(x+1\right)-\frac{4}{5}x=0\)
\(\Leftrightarrow\frac{2}{5}x+\frac{2}{5}-\frac{4}{5}x=0\)
\(\Leftrightarrow-\frac{2}{5}x=-\frac{2}{5}\Leftrightarrow x=1\)
27 tháng 4 2018
a) x-1/3=5/14.(-7/6)
x-1/3=-5/12
x=-5/12+1/3
x= -1/12
b) 3/4+1/4x=0,2
1/4x=0,2-3/4
1/4x=-11/20
x=-11/20:1-4
x=-11/5
c) 1/12.x^2=1.1/2
1/12.x^2=1/2
x^2= 1/2:1/12
x^2=6
=> x=căn bậc của 6
Chúc bn hok tốt
DT
27 tháng 4 2018
a)\(x-\frac{1}{3}=\frac{5}{14}\cdot\left(\frac{-7}{6}\right)\)
\(x-\frac{1}{3}=\frac{-5}{12}\)
\(x=\frac{-5}{12}+\frac{1}{3}\)
\(x=\frac{-5}{12}+\frac{4}{12}\)
\(x=\frac{-1}{12}\)
b)\(\frac{3}{4}+\frac{1}{4}\cdot x=0,2\)
\(\frac{3}{4}+\frac{1}{4}\cdot x=\frac{1}{5}\)
\(\frac{1}{4}\cdot x=\frac{1}{5}-\frac{3}{4}\)
\(\frac{1}{4}\cdot x=\frac{4}{20}-\frac{15}{20}\)
\(\frac{1}{4}\cdot x=\frac{-11}{20}\)
\(x=\frac{-11}{20}\cdot4\)
\(x=-\frac{11}{5}\)
c)\(\frac{1}{12}\cdot x^2=1\cdot\frac{1}{3}\)
\(\frac{1}{12}\cdot x^2=\frac{1}{3}\)
\(x^2=\frac{1}{3}\cdot12\)
\(x^2=4=\left(\pm2\right)^2\)
\(x=\pm2\)
\(x.3\frac{1}{4}+\left(\frac{-7}{6}\right)x-1\frac{2}{3}=\frac{5}{12}\)
\(x.\frac{13}{4}+\left(\frac{-7}{6}\right)x-\frac{5}{3}=\frac{5}{12}\)
\(x\left[\frac{13}{4}+\left(\frac{-7}{6}\right)\right]-\frac{5}{3}=\frac{5}{12}\)
\(x\frac{25}{12}-\frac{5}{3}=\frac{5}{12}\)
\(x\frac{25}{12}=\frac{5}{12}+\frac{5}{3}\)
\(x\frac{25}{12}=\frac{25}{12}\)
\(x=\frac{25}{12}:\frac{25}{12}\)
\(x=1\)