Question

If the solution of an equation is x=-2 what could the original equation be?

Answer 1

You can formulate anything here as long as you can substitute x for -2 and you get the right answer (IE both sides of the equation balance).

Examples:
x + 2 = 0
x + 4 = 2
or even something like
x + y = -2 - y

Answer 2

There are an infinite number of possibilities.
Here's one:

6x + 107 = -77x - 59