Answer:
1) When x is 1, y is 4, and vice versa
2) When x is -6, y is 42, and when x is 7, y is 114
3) When x is -2, y is 2, and when x is 8, y is 42
Explanation:
1)

which can be rearranged as
.
Substituting this lone y into the first equation, you get:

Move everything to one side:

Factor:



2)
which can be rearranged as
.

Let's use elimination this time and subtract the first equation from the second:

Factor:



3)


Let's set the two equations equal to each other through substitution:

Move everything to one side:

Factor:



Hope this helps!