15x : 5y = 45y
=> 15x = 45y x 5y = ( 45 x 5 ) y = 225y
=> 15x = 225y
=> 15x - 225y = 0
=> x = 0 y = 0
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Bạn vào đây tham khảo nhé !!!
\(15^x.5^y=45^y\)
\(15^x:5^y=\left(225:5\right)^y\)
\(15^x:5^y=225^y:5^y\)
\(\Rightarrow15^x=225^y\)
\(15^x=\left(15^2\right)^y\)
\(\Rightarrow x=2y\)
\(\frac{x}{y}=2\)