\(\frac{8^{15}.3^{16}}{4^{22}.9^8}=\frac{\left(2^3\right)^{15}.3^{16}}{\left(2^2\right)^{22}.\left(3^2\right)^8}=\frac{2^{45}.3^{16}}{2^{44}.3^{16}}=2\)

\(\frac{8^{15}.3^{16}}{4^{22}.9^8}=\frac{\left(2^3\right)^{15}.3^{16}}{\left(2^2\right)^{22}.\left(3^2\right)^8}=\frac{2^{45}.3^{16}}{2^{44}.3^{16}}=2\)

2k.3k.5k= -1920

2.3.5.k³= -1920

 30   .k³= -1920

         k³= -1920:30

         k³= -64

=>k=4

k mik nha

k là cái chi . Mình chẳng hiểu 

\(\frac{15}{7}-\frac{x}{2}=\frac{1}{2}\)

  \(\frac{x}{2}=\frac{15}{7}-\frac{1}{2}\)

    \(\frac{x}{2}=\frac{23}{14}\)

     \(14x=23.2\)

      \(14x=46\)

           \(x=\frac{23}{7}\)

\(\frac{15}{7}-\frac{x}{2}=\frac{1}{2}\)

\(\Rightarrow\frac{x}{2}=\frac{15}{7}-\frac{1}{2}\)

\(\Rightarrow\frac{x}{2}=\frac{23}{14}\)

\(\Rightarrow\frac{7x}{14}=\frac{23}{14}\)

\(\Rightarrow7x=23\Rightarrow x=\frac{23}{7}\)

Ta có:

\(\frac{x}{2}=\frac{y}{3}=\frac{z}{5}\)

=> \(\frac{x}{2}.\frac{x}{2}.\frac{x}{2}=\frac{y}{3}.\frac{y}{3}.\frac{y}{3}=\frac{z}{5}.\frac{z}{5}.\frac{z}{5}=\frac{x}{2}.\frac{y}{3}.\frac{z}{5}\)

=> \(\frac{x^3}{8}=\frac{y^3}{27}=\frac{z^3}{125}=\frac{810}{30}=27\)

=> \(\hept{\begin{cases}x^3=27.8=6^3\\y^3=27.27=9^3\\z^3=27.125=15^3\end{cases}}\)=> \(\hept{\begin{cases}x=6\\y=9\\z=15\end{cases}}\)

Vậy ...

x=0

y=0

các bạn có thể trình bày cách làm được ko !!