Given : $$x+y=4$$ and $$x^2+y^2=14$$ ----------------(i)
Squaring both sides, we get :
=> $$(x+y)^2=(4)^2$$
=> $$x^2+y^2+2xy=16$$
=> $$14+2xy=16$$
=> $$2xy=16-14=2$$
=> $$xy=1$$
=> $$y=\frac{1}{x}$$
Substituting it in equation (i), => $$x+\frac{1}{x}=4$$
=> $$x^2-4x+1=0$$
=> $$x=\frac{4\pm\sqrt{(-4)^2-4(1)(1)}}{2}$$
=> $$x=\frac{4\pm\sqrt{12}}{2}$$
=> $$x=\frac{4\pm2\sqrt{3}}{2}$$
=> $$x=2\pm\sqrt3$$
$$\because$$ $$x>y$$ => $$x=2+\sqrt3$$ and $$y=2-\sqrt3$$
=> Ans - (C)
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