Question

add.
(3m + 9) + (7m + 4)

Explanation:

Step1: Remove parentheses

$(3m + 9) + (7m + 4)=3m + 9 + 7m + 4$

Step2: Combine like terms

Combine the $m$ terms: $3m+7m = 10m$
Combine the constant terms: $9 + 4=13$
So the result is $10m + 13$

Answer:

$10m + 13$