Answer:
Therefore the friends will have to buy 511 feet of fence (rounding up) or 510 feet of fence ( to the nearest foot).
Step-by-step explanation:
i) perimeter of rectangular yard = 319 feet
ii) perimeter of yard of friends 
iii) Therefore the friends will have to buy 511 feet of fence or 510 feet of fence ( to the nearest foot).
400x to the power of 2 + 480x + 144
9% decrease because 145-132=13
13=9% of 145
Answer:
6.9
7.-5
8.-10
Step-by-step explanation: