Question

[Ngọc Nhi]

tìm x,y,z 

\(\hept{\begin{cases}3x=5y,\frac{5x}{2}=\frac{7z}{3}\\xz=47250\end{cases}}\)

ai nhanh giúp mình với mik tik cho

Answer 1

[Phạm Tuấn Đạt]

Đặt \(\frac{5x}{2}=\frac{7z}{3}=k\Rightarrow x=\frac{2k}{5};z=\frac{3k}{7}\)

Có \(x.z=47250\)

\(\Rightarrow\frac{2k}{5}.\frac{3k}{7}=47250\Rightarrow\frac{6k^2}{35}=47250\Rightarrow k^2=47250.35:6=275625\Rightarrow k=525\)

\(\Rightarrow x=525.2:5=210\)

\(z=525.3:7=225\)

Do \(3x=5y\Rightarrow210.3=5y\Rightarrow630=5y\Rightarrow y=630:5=126\)