There are 0, or no solutions to these equations. If you rearrange each equation to look like an equation of a line, you will have the two lines:
y = x -1 and y = x + 1, which are two parallel lines. They do not intersect at any point, so there is no solution.
Your question does not make sense.
Infinite, both equations are equivalent and all possible solutions can be represented on the graph y = 4 - x
There are no whole solutions
many solutions
There are 120 solutions.
1 solution
1
many solutions
2
Two solutions and they are:- x = 0 and y = 3
It has two equal solutions of 2
One solution.