Answer:
see explanation
Step-by-step explanation:
4a + 8 4
2a² + 8a 2a
12a² - 8a 4a
4 - 6a 2
c=-5
2c-3=12-2c+7c
2c-3=12+5c
2c-5c-3=12
-3c-3=12
-3c=12+3
-3c=15
c=15/-3
Answer: the sum is 1.08