Simplify - 9 (1-10n) - 2 (3n+9)

3 (28 n - 9)

Step-by-step explanation:

Simplify the following:

-9 (1 - 10 n) - 2 (3 n + 9)

-9 (1 - 10 n) = 90 n - 9:

90 n - 9 - 2 (3 n + 9)

-2 (3 n + 9) = - 6 n - 18:

90 n + - 6 n - 18 - 9

Grouping like terms, 90 n - 6 n - 18 - 9 = (90 n - 6 n) + (-9 - 18):

(90 n - 6 n) + (-9 - 18)

90 n - 6 n = 84 n:

84 n + (-9 - 18)

-9 - 18 = - 27:

84 n + - 27

Factor 3 out of 84 n - 27:

Answer: 3 (28 n - 9)