Answer:
c = -1
Step-by-step explanation:
3(c+5)=12
3 × c = 3c
3 × 5 = 15
3c + 15 = 12
- 15 -15
3c = -3
c = -3 ÷ 3 = -1
Check:
3(-1+5)=12
-3 + 15 = 12