Question

x/2 = y/3 = z/5 ; xyz =810

Answer 1

Đặt \(\dfrac{x}{2}=\dfrac{y}{3}=\dfrac{z}{5}=k\)

=>x=2k; y=3k; z=5k

xyz=810

=>\(2k\cdot3k\cdot5k=810\)

=>\(30k^3=810\)

=>\(k^3=27=3^3\)

=>k=3

\(x=2\cdot3=6;y=3\cdot3=9;z=5\cdot3=15\)

Answer 2

e

 

Answer 3

Đặt \(\dfrac{x}{2}=\dfrac{y}{3}=\dfrac{z}{5}=k\Rightarrow\left\{{}\begin{matrix}x=2k\\y=3k\\z=5k\end{matrix}\right.\)

Thay vào \(xyz=810\)

\(\Rightarrow2k.3k.5k=810\)

\(\Rightarrow30k^3=810\)

\(\Rightarrow k^3=27\)

\(\Rightarrow k=3\)

\(\Rightarrow\left\{{}\begin{matrix}x=2.3=6\\y=3.3=9\\z=5.3=15\end{matrix}\right.\)