\(tìm\)\(x;y\)\(để\)
\(a.\)\(\frac{5}{x}\)\(=\)\(\frac{-y}{7}\) \(và\)\(y\)\(>\)\(0\)
\(b.\)\(\frac{x}{4}\)\(=\)\(\frac{y}{3}\)\(và\)\(x+y=14\)
\(làm\)\(chi\)\(tiết\)\(cho\)\(mình\)\(nhé\)
\(ai\)\(xong\)\(trước\)\(và\)\(chính\)\(xác\)\(nhất\)\(thì\)\(mình\)\(sẽ\)\(K\)\(cho.\)\(Thanks\)\(!!!\)