The line that passes through the given point may be stated as
y - y1 = m(x - x1)
where (x1, y1) and (x2, y2) = (-6,5) and (6,-7)
m = (y2 - y1)/(x2 - x1)
= (-7 - 5)/(6 - -6)
= -12/12
= -1
Hence the equation of the line that passes through the given points is
(y - 5) = -1(x - -6)
y - 5 = - x - 6
y = -x - 6 + 5
y = -x - 1