Answer
(a) The point $(6,0)$ does not lie on the graph of $2x^2+5y^2=8$
(b) The point $(0,4)$ does not lie on the graph of $2x^2+5y^2=8$
Work Step by Step
$2x^2+5y^2=8$
(a) Point: $(6,0)$:
$2(6)^2+5(0)^2=2(36)+5(0)=72\ne8$
(b) Point: $(0,4)$:
$2(0)^2+5(4)^2=2(0)+5(16)=80\ne8$