Explanation:
in what form do you need the equations ?
I assume you need the scope-intercept form :
y = ax + b
"a" is the slope, "b" is the y-intercept (the y-value when x = 0).
the slope is the ratio
y coordinate difference / x coordinate difference
when going from one point on the line to another.
to do that we look for "good" points for each line - that means points with integer coordinates.
I see e.g. the intersection point of the 2 lines : (-3, 1).
then for the upper line I see also (0, 3), and for the lower line (0, -2).
so, for the upper line (-3, 1) to (0, 3) we see
x changes by + 3 (from -3 to 0).
y changes by +2 (from 1 to 3).
the scope of the upper line is then +2/+3 = 2/3.
the y-intercept is y = 3 via the point (0, 3).
and the equation is
y = 2x/3 + 3
for the lower line (-3, 1) to (0, -2) we see
x changes by +3 (from -3 to 0).
y changes by -3 (from +3 to -0.9)
the slope of this lower line is then -3/+3 = -1.
the y-intercept is y = -2 via the point (0, -2).
and the equation is
y = -x - 2