Answer
Substitution method
Work Step by Step
$$3x + 2y = -2$$ $$y = -2x$$
A system composed of these equations would be easier to solve using the substitution method, as the value of $y$ in terms of $x$ is already given. Moreover, since it is just a single term $(-2x)$, then substituting this value to the original equation would not pose any complexity or difficulty.
For instance,
$$3x + 2y = -2$$ $$3x + 2(-2x) = -2$$ $$3x -4x = -2$$ $$x=2$$