ANSWER: 
The length of the third side of a triangular playground at a shopping mall is 15 feet. 
SOLUTION: 
Given, perimeter of a triangular playground at a shopping mall = 48 feet 
Length of one of the side of that triangular playground = 19 feet 
 Length of another side of that triangular playground = 14 feet 
Now, we need to find the length of the third side of the triangle. 
We know that the formula for perimeter of triangle is given as 
 p = a + b + c 
Where, p is the perimeter of the triangle 
a is the length of first side of triangle 
b is the length of second side of triangle 
c is the length of third side of triangle 
We need to find the length of third side 
Let a = 19 feet ; b = 14feet ; c =? 
p = a + b + c 
48 = 19 + 14 + c 
48 = 33 + c 
c = 48 – 33 
c = 15feet 
Hence, length of the third side of a triangular playground at a shopping mall is 15 feet