How to simplify

-6k + 7k

12r - 8 - 12

n - 10 + 9n - 3

-4x-10x

-r - 10r

Solve by adding or subtracting like terms. (Ex. 2k + 4k = 6k; 9 + 7 = 16)

- 6k + 7k = 1k = k

(7 - 6 = 1)

12r - 8 - 12 = 12r - 20

(8 + 12 = 20 but sign is negative) 12r will stay the same because there are no terms with a letter r.

n - 10 + 9n - 3 = 9n + n - 10 - 3 = 10n - 10 - 3 = 10n - 13

(n = 1 so 9 + 1 = 10; 10 + 3 = 13 but negative sign)

- 4x - 10x = 14x

(10 + 4 = 14)

- r - 10r = 11r

(r = 1 so 10 + 1 = 11)