From the given we see immediately that the slope of this line is -1. The slope of a line perpendicular to this one is +1, which is the negative reciprocal of -1. The slope-intercept form is y = mx + b. To find b, the y-intercept, we make the following substitutions: m = -1, y = -2, x = -2:
-2 = +1(-2) + b, or +1 = 2 + b, or b = -1
and so the desired equation is y = x - 1 (third answer choice)
