Question

tìm x 

a) x: 27=3,6

b)\(\dfrac{2x+1}{-27}\) =\(\dfrac{-3}{2x+1}\)

Answer 1

a/\(x:27=3,6\)
\(\Rightarrow x=97,2\)
b/\(\dfrac{2x+1}{-27}=\dfrac{-3}{2x+1}\)
\(\Rightarrow\left(2x+1\right)^2=81\)
\(\Rightarrow\left[{}\begin{matrix}2x+1=9\\2x+1=-9\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}2x=8\\2x=-10\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=4\\x=-5\end{matrix}\right.\)
Vậy \(x\in\left\{4;-5\right\}\)

Answer 2

a) x=3,6\(\times\) 27=97,2

 

 

 

Answer 3

a,x:27=3,6

x=3,6:27

x\(\approx\)0,13

\(\Rightarrow\)x=0,1(3)