Question

tìm x biết\(\frac{x+3}{3}=\frac{27}{x+3}\)

Answer 1

lên mạng đi 

Answer 2

\(\frac{x+3}{3}=\frac{27}{x+3}\left(ĐKXĐ:x\ne-3\right)\)

\(\Leftrightarrow\left(x-3\right)^2=81\)

\(\Leftrightarrow\orbr{\begin{cases}x-3=9\\x-3=-9\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=12\\x=-6\end{cases}}\)( Tm ĐKXĐ ) 
Vậy ...

Answer 3

Theo bài ra ta cs (x+3).(x+3)=3.27

=>(x+3)^2=81

=>x+3=9

=>x=6

Vậy...

Answer 4

(x + 3 ) . (x + 3) = 27 . 3

(x + 3)² = 81

x + 3 = 9²

x + 3 = 9

 x = 6