Since A‘(-1,1) is on the line y=-x, reflecting it about the line doesn't change its coordinate, so A's coordinate is (-1,1). Reflecting B'(-2,1) about y=-x switches both the sign and the number of x and y, so B=(-1,2), and C'(-1,0) becomes C(0,1). Drawing out the graph with the points and the line helps.
With this problem, subtract 7 from both sides to get
17< y
So any number that is greater than 17 is a value that would make it true....19, 24, 35, 100, 39,1028
If tan x = .56, then cot x is 1.79