-3(m+6)-(11+9m)
distribute
-3m -3*6 -11-9m
-3m -18 -11-9m
-12m -29
First use the distributive property to multiply the first set of parentheses with the -3 and the second parentheses flip the signs because its negative
(-3m-18)+(-11-9m)
Then remove parentheses because it is addition and combine like terms
-12m - 29
