PEMDAS is a acronym for remembering what to do first in these types of equations
P---- Parenthesis
E---- Exponents
M---- Mutipulcation
D---Division
A---Add
S---Subract
Distributive property is when there is nothing to simplyfly in the parenteses but there is a number before it such as
8(x+2) in which we distribute 8 to x and 8 to 2
10x-4(x+5) +9
So, in this equation we see a Prarenthesis, which means we have to deal with that first, but inside the Parenthesis there is nothing that we can do.
But there is a -4 outside the Parenthesis that we can distribute to get rid of it
10x-4x-20+9
Now we combine like terms
10x-4x
-20+9
Therefore: 6x-11