Question

An equation in the system is y = x + 1. What is the other equation in the system if the solution is only at (0, 1)?

Answer 1

y = 1 ?

Answer 2

then x can only be 0, so that's the only solution (0,1)

Answer 3

There is an infinite number of equations that will give that single solution.
Do you have choices?

Answer 4

This is a graph of the line whose equation is y = x + 1

Answer 5

All the lines drawn in black that intersect the given line y = x + 1 at point (0, 1) could be the second equation of the problem.
As you can see there is an infinite number of them.