Simplify.

a - {4b - [a - (5b - c) + 3c - (a - b - 9c)]}

a)-a - 8b + 13c
b) a - 8b + 13c
c) a - 2b + 13c
d)-a - 2b + 13c

If you would like to simplify a - {4b - [a - (5b - c) + 3c - (a - b - 9c)]}, you can do this using the following steps:

a - {4b - [a - (5b - c) + 3c - (a - b - 9c)]} = a - {4b - [a - 5b + c + 3c - a + b + 9c]} = a - {4b - [- 4b + 13c]} = a - {4b + 4b - 13c} = a - {8b - 13c} = a - 8b + 13c

The correct result would be b) a - 8b + 13c.

To simplify a - {4b - [a - (5b - c) + 3c - (a - b - 9c)]} ,  we group the like terms and perform addition adn subtraction to these grouped terms. no multiplication nor division is applied. In thi case, the grouping results to 
a - 4b + a - 5b +c + 3c - a + b + 9c = a -8 b + 13c. answer is B 

Answers4.) -1/205.) -1/406.) -55/127.) -3/4

I'm not sure but i think it's 1670km/h