Answer
$$\left( { - 1,3} \right)$$
Work Step by Step
$$\eqalign{
& \,2x + y = 1\,\,\,\,\,\,\,\,\,\left( {\bf{1}} \right) \cr
& {x^2} + {y^2} = 10\,\,\,\,\,\,\left( {\bf{2}} \right) \cr
& \cr
& {\text{We know the point }}\left( {x,3} \right),{\text{ then }}y = 3 \cr
& {\text{Substitute }}y = 3{\text{ into the equation }}\left( {\bf{1}} \right){\text{ and solve for }}x \cr
& \,2x + 3 = 1 \cr
& \,2x = - 2 \cr
& x = - 1 \cr
& \cr
& {\text{Therefore, one of the solutions onf the nonlinear systems is }} \cr
& \left( { - 1,3} \right) \cr} $$
