Answer: She would need 60 ft of border material.
Step-by-step explanation: Olga has a triangular flower bed, which means her flower bed is three sided. Also it has been stated that she has 20 feet of border material available. which will fit perfectly around the bed. This also means the perimeter of her flower bed is 20 feet.
Assuming the sides of her flower bed are labeled as a, b and c. Then a plus b plus c would equal 20, since the perimeter is the addition of all sides of the triangle.
However, she intends to triple the length of each side of the flower bed, and that would translate into the sides being 3a, 3b and 3c respectively. This effectively triples the length of the perimeter which is shown as,
Perimeter = a + b + c
20 = a + b + c
3(20) = 3a + 3b + 3c
60 = 3a + 3b + 3c
Therefore, she is going to need more border material and that is calculated as 60 feet.