a) Ta có: \(\frac{5}{8}=\frac{x}{14}\)
\(\Leftrightarrow x=\frac{5\cdot14}{8}=\frac{70}{8}=8,75\)
Vậy: x=8,75
b) Ta có: \(\frac{x}{-5}=\frac{-5}{x}\)
\(\Leftrightarrow x^2=25\)
\(\Leftrightarrow x\in\left\{5;-5\right\}\)
Vậy: \(x\in\left\{5;-5\right\}\)
a, \(\frac{5}{8}=\frac{x}{14}\\ \Rightarrow8x=5.14=70\\ \Rightarrow x=8,75\)
Vậy x = 8,75
b, \(\frac{x}{-5}=\frac{-5}{x}\\ \Rightarrow x^2=\left(-5\right)\left(-5\right)=25\\ \Rightarrow\left[{}\begin{matrix}x=5\\x=-5\end{matrix}\right.\)
Vậy \(x\in\left\{5;-5\right\}\)
