Question

pleaseeeeeee.....va rog mult....

Answer 1

sper ca te.am ajutat

Answer 2

a)

[tex]\it \dfrac{x}{3}=\dfrac{y}{4} \ \ \ \ (1) \\ \\ \\ \dfrac{y}{4}=\dfrac{z}{5} \ \ \ \ (2) \\ \\ \\ (1), (2) \Rightarrow \dfrac{x}{3}=\dfrac{y}{4} =\dfrac{z}{5} =k \Rightarrow \begin{cases}\it x = 3k \\ \\ \it y=4k \\ \\ \it z = 5k\end{cases} \ \ \ \ (*)[/tex]

[tex]\it x\cdot y\cdot z=480 \stackrel{(*)}{\Longrightarrow}3k\cdot4k\cdot5k = 480 \Rightarrow 60\cdot k\cdot k\cdot k=480|_{:60} \Rightarrow \\ \\ \\ \Rightarrow k\cdot k\cdot k= 8 \Rightarrow k\cdot k\cdot k= 2\cdot2\cdot2 \Rightarrow k=2\stackrel{(*)}{\Longrightarrow} \begin{cases}\it x = 3\cdot2=6 \\ \\ \it y=4\cdot2=8 \\ \\ \it z = 5\cdot2=10\end{cases}[/tex]