Answer:
y = - x
Explanation:
The equation of a line passing through the origin is
y = mx ( m is the slope )
Calculate m using the slope formula
m =

with (x₁, y₁ ) = (- 2, 2) and (x₂, y₂ ) = (2, - 2) ← 2 points on the line
m =
=
= - 1 , thus
y = - x ← equation of line