Answer:
91.14 feet
Step-by-step explanation:
Given:
In a park,a sidewalk is built around the edge of a circular pond.
The sidewalk is 7 feet wide, and the pond measure 15 feet across.
Question asked:
What amount of railing would be needed to go completely around the outer edge of the sidewalk?
Solution:
From distance from one edge of the pond to the another = 15 feet
That means diameter of the pond = 15 feet
And width of the sidewalk = 7 feet all around
combined diameter = 15 + 7 + 7 = 29 feet
Radius,r = 
That means distance between outer edge of the sidewalk to the center of the circular pond = 14.5 feet
Now, we will have to find circumference of outer circular edge of sidewalk:


Therefore, 91.14 feet would be needed to go around the outer edge of the sidewalk.
I: 12x-5y=0
II:(x+12)^2+(y-5)^2=169
with I:
12x=5y
x=(5/12)y
-> substitute x in II:
((5/12)y+12)^2+(y-5)^2=169
(25/144)y^2+10y+144+y^2-10y+25=169
(25/144)y^2+y^2+10y-10y+144+25=169
(25/144)y^2+y^2+144+25=169
(25/144)y^2+y^2+169=169
(25/144)y^2+y^2=0
y^2=0
y=0
insert into I:
12x=0
x=0
-> only intersection is at (0,0) = option B
The answer is in my attachment