We must solve the following system of equation:

Solving by elimination method.
If we add the first equation wih the second one, we obtain

which is equal to

If we move y to the left hand side, we have

and it reads

We obtained the first result y=4. Now, we can substitute this value into one of the two equation. If we substitute y=4 in the first equation, we have

which gives x=-4. Finally, the answer is x=-4 and y=4. The coordinate of this solution is (-4,4).