Question 1052226
Can you combine like-terms of c ?  
Not yet, but simplifications are necessary.


PEMDAS


Parentheses?  Nothing you do with c-8.  It stays that way until later.


Exponentiation?  None to do.


Multiplication?  Yes.  Look at the use of Distributive Property for the first shown product.
{{{12c-12*8+15+4c=1711}}}

and then
12c-96+15+4c=1711


Divisions?  None.


Additions?  Yes, but you also need to intuitively be able to use Commutative Property for Addition, and not be bothered by interpretation for Subtractions.  Knowing how signed numbers work would help, but likely still new to you.
-
{{{12c+4c-96+15=1711}}}


{{{16c-96+15=1711}}}


{{{16c-81=1711}}}
In fact Subtraction WAS done last, but ....



You still want to isolate c.


Without any explanation, I show 
{{{16c=1711+81}}}
{{{16c=1792}}}
{{{highlight(c=112)}}}