Answer:
8a+2b+c
Step-by-step explanation:
13a-4b+8c
-(5a-6b+7c)
simplify second equation: -5a+6b-7c (multiplying -1 by each number)
now solve
13a-4b+8c
-5a+6b-7c
= 13a-5a-4b+6b+8c-7c (combining both equations, and like terms)
solve:
8a+2b+1c
= 8a+2b+c
