Answer
{$(1,0),(-1,0)$}
Work Step by Step
After adding the given two equations, we get $8x^2=8$
or, $x^2=1$;
or $x=\pm 1$
From first equation $4x^2-y^2=4$ when $x=1$, we have $y=0$
From first equation $4x^2-y^2=4$ when $x=-1$, we have $y=0$
Thus, solution set is {$(1,0),(-1,0)$}