Question

subtract the sum of 3a-4b+5c and -5a+7b-9c from a-b-c

Answer 1

(3a-4b+5c)+(-5a+7b-9c)
3a-4b+5c-5a+7b-9c
(3a-5a)-(4b-7b)+(5c-9c)
-2a+3b-4c
a-b-c-(-2a+3b-4c)
a-b-c+2a-3b+4c
3a-4b+3c
this is your answer...

Answer 2

heya mate

your answer is in this pic,

hope this helps