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Solve the simultaneous equations : (log_{2} x – log_{2} y = 2 ; log_{2} (x…

Solve the simultaneous equations : (log_{2} x – log_{2} y = 2 ; log_{2} (x – 2y) = 3)

Explanation

(log_{2} x – log_{2} y = 2 implies log_{2} (frac{x}{y}) = 2 )

(frac{x}{y} = 2^{2} = 4 implies x = 4y … (1))

(log_{2} (x – 2y) = 3 implies x – 2y = 2^{3} = 8 … (2))

Putting (1) into (2),

(4y – 2y = 8 implies 2y = 8)

(y = 4)

(x = 4y implies x = 4(4) = 16)

(x = 16 ; y = 4)