y x 3/5 - y :5 =4
y x 3/5 - y x 1/5 = 4
y x (3/5 - 1/5) = 4
y x 2/5 =4/1
y =4/1:2/5
y =10
y x\(\frac{3}{5}\)-y :5=4
y x\(\frac{3}{5}\)-y x\(\frac{1}{5}\)=4
y x(\(\frac{3}{5}\)-\(\frac{1}{5}\))=4
y x \(\frac{2}{5}\)=4 y =4 :\(\frac{2}{5}\)=4 x \(\frac{5}{2}\)=10
mình nhanh nhất! chọn mình nhé! ^o^