(-1;3), (3;x)

x = 1

(9;-6), (4;a)

a = 6

(4;5), (y;8)

y = -10

(c;9), (-6;-2)

c = -3

(1;n), (-5;1)

n = 5

(8;d), (-1;-4)

d = -2

(m;7), (3, -3)

m = 7

(1;-5), (5; k)

k = 1

(3;2), (p;6)

p = -4

(4;s), (-6;-8)

s = -3