Answer:
64 feet
Step-by-step explanation:
1. perimeter would be 2x the length + 2x the width.
2. that would be 2(x+8) + 2(12)
3. simplified it would be 2x+16+24
4. combine like terms would be 2x+40
5. substitute 12 for x
6. 2(12)+40
7. 24+40
8. 64 feet