Hello:
the equation is : y = ax+b
the slope is a : a×(1) = -1......(
perpendicular to a line : -x+y = 7 or y =x+7 with a slope of 1)
a =-1 y=-x+b
the line that passes through (-1, -1) : -1 =- (-1)+b
b =-2
the equation is : y =-x-2