If x² + 4y² = 4xy, then x : y is -

A. 1 : 1

B. 1 : 2

C. 2 : 1

D. 1 : 4

Answer: Option C

Solution(By Examveda Team)

$$\eqalign{ & = {x^2} + 4{y^2} = 4xy \cr & \Rightarrow {x^2} - 4xy + 4{y^2} = 0 \cr & \Rightarrow \left( {x - 2{y^2}} \right) = 0 \cr & \Rightarrow x = 2y \cr & \Rightarrow \frac{x}{y} = 2 \cr & \Rightarrow x:y = 2:1 \cr} $$