Is the given number a solution of the equation?

9k = 10 - k; -1

-7r - 15 = -2r; -3

-3p = 4p + 35; -5

8 -e = 2e - 16; 8

5 - 15s = 8 - 16s; 3

2(x - 2) - 5x = 5(2 - x); 7

6a + 3 = 3(3a - 2); 4