Question

Tìm x biết: 

a) \(\left(\frac{2x}{5}-1\right):\left(-5\right)=\frac{1}{4}\)

b) \(\left(-5,75\right):x=\frac{14}{23}\)

Answer 1

a) \(\frac{2x}{5}-1=\frac{1}{4}.\left(-5\right)=-\frac{5}{4}\)

\(\frac{2}{5}.x=\left(-\frac{5}{4}\right)+1=-\frac{1}{4}\)

\(x=-\frac{1}{4}:\frac{2}{5}=-\frac{5}{8}\)

b) \(x=\left(-5,75\right):\frac{14}{23}=-\frac{23}{4}:\frac{14}{23}=-\frac{529}{56}\)

Answer 2

a) \(\Rightarrow\left(2x:5-1\right)=\frac{1}{4}.\left(-5\right)=-\frac{5}{4}\)

\(\Rightarrow2x:5=-\frac{5}{4}+1=-\frac{1}{4}\)

\(\Rightarrow2x=-\frac{1}{4}.5=-\frac{5}{4}\)

\(\Rightarrow x=-\frac{5}{4}:2=-\frac{5}{8}\)

b) \(\Rightarrow x=-5.75:\frac{14}{23}=-\frac{529}{56}\)